Staple cartridge comprising a tissue thickness compensator

ABSTRACT

A staple cartridge is disclosed. The staple cartridge can comprise a cartridge body comprising a deck and a bottom surface opposite the deck. The staple cartridge can comprise a plurality of staple cavities, wherein each staple cavity extends into the cartridge body from the deck to the bottom surface. Additionally, a plurality of wells can be defined into the staple cartridge from the deck to a lowermost surface of the well. A plurality of staples can be removably positioned in the staple cavities. The staple cartridge can comprise a tissue thickness compensator releasably secured to the cartridge body, wherein the tissue thickness compensator comprises a compensator body and a plurality of extensions extending from the compensator body into the wells, wherein at least one extension is compressed within one of the wells. Each well can surround at least one staple cavity and/or can extend between at least two staple cavities.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 16/441,564, entitledEND EFFECTOR INCLUDING DIFFERENT TISSUE GAPS, filed Jun. 14, 2019, nowU.S. Patent Application Publication No. 2020/0000469, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 16/105,387, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR, flied Aug. 20, 2018, whichissued on Feb. 2, 2021 as U.S. Pat. No. 10,905,418, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 14/587,192, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR, filed Dec. 31, 2014, whichissued on Aug. 21, 2018 as U.S. Pat. No. 10,052,104, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 14/516,277, entitled STAPLE CARTRIDGECOMPRISING AN ADJUNCT MATERIAL, filed Oct. 16, 2014, which issued onMarch 27, 2018 as U.S. Pat. No. 9,924,944, the entire disclosures ofwhich are hereby incorporated by reference herein.

BACKGROUND

The present invention relates to stapling instruments and, in variousembodiments, to a surgical stapling instrument for producing one or morerows of staples.

A stapling instrument can include a pair of cooperating elongate jawmembers, wherein each jaw member can be adapted to be inserted into apatient and positioned relative to tissue that is to be stapled and/orincised. In various embodiments, one of the jaw members can support astaple cartridge with at least two laterally spaced rows of staplescontained therein, and the other jaw member can support an anvil withstaple-forming pockets aligned with the rows of staples in the staplecartridge. Generally, the stapling instrument can further include apusher bar and a knife blade which are slidable relative to the jawmembers to sequentially eject the staples from the staple cartridge viacamming surfaces on the pusher bar and/or camming surfaces on a wedgesled that is pushed by the pusher bar. In at least one embodiment, thecamming surfaces can be configured to activate a plurality of stapledrivers carried by the cartridge and associated with the staples inorder to push the staples against the anvil and form laterally spacedrows of deformed staples in the tissue gripped between the jaw members.In at least one embodiment, the knife blade can trail the cammingsurfaces and cut the tissue along a line between the staple rows.Examples of such stapling instruments are disclosed in U.S. Pat. No.7,794,475, entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLEMEMBERS FOR SECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FORDEPLOYING THE SAME, the entire disclosure of which is herebyincorporated by reference herein.

The foregoing discussion is intended only to illustrate various aspectsof the related art in the field of the invention at the time, and shouldnot be taken as a disavowal of claim scope.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features of the embodiments described herein are set forth withparticularity in the appended claims. The various embodiments, however,both as to organization and methods of operation, together withadvantages thereof, may be understood in accordance with the followingdescription taken in conjunction with the accompanying drawings asfollows:

FIG. 1 is a perspective view of a staple cartridge in accordance with atleast one embodiment comprising a stepped deck surface;

FIG. 2 is a detail view of the deck surface of the staple cartridge ofFIG. 1;

FIG. 3 is a plan view of the staple cartridge of FIG. 1;

FIG. 4 is an elevational view of the staple cartridge of FIG. 1;

FIG. 5 is a cross-sectional view of the staple cartridge of FIG. 1 takenalong line 5-5 in FIG. 3;

FIG. 6 is a cross-sectional view of the staple cartridge of FIG. 1 takenalong line 6-6 in FIG. 3;

FIG. 6A is a perspective view of a layer usable with the staplecartridge of FIG. 1;

FIG. 7 is a perspective view of a staple cartridge in accordance with atleast one embodiment comprising a ridged deck surface;

FIG. 8 is a detail view of the deck surface of the staple cartridge ofFIG. 7;

FIG. 9 is a plan view of the staple cartridge of FIG. 7;

FIG. 10 is an elevational view of the staple cartridge of FIG. 7;

FIG. 11 is a cross-sectional view of the staple cartridge of FIG. 7taken along line 11-11 in FIG. 9;

FIG. 12 is a cross-sectional view of the staple cartridge of FIG. 7taken along line 12-12 in FIG. 9;

FIG. 12A is a perspective view of a layer usable with the staplecartridge of FIG. 7;

FIG. 13 is a perspective view of a staple cartridge in accordance withat least one embodiment comprising wells defined in a deck surface;

FIG. 14 is a detail view of the deck surface of the staple cartridge ofFIG. 13;

FIG. 15 is a plan view of the staple cartridge of FIG. 13;

FIG. 16 is an elevational view of the staple cartridge of FIG. 13;

FIG. 17 is a cross-sectional view of the staple cartridge of FIG. 13taken along line 17-17 in FIG. 15;

FIG. 18 is a cross-sectional view of the staple cartridge of FIG. 13taken along line 18-18 in FIG. 15;

FIG. 18A is a perspective view of a layer usable with the staplecartridge of FIG. 13;

FIG. 19 is a perspective view of a staple cartridge in accordance withat least one embodiment comprising a wavy deck surface;

FIG. 20 is a detail view of the deck surface of the staple cartridge ofFIG. 19;

FIG. 21 is a plan view of the staple cartridge of FIG. 19;

FIG. 22 is an elevational view of the staple cartridge of FIG. 19;

FIG. 22A is a perspective view of a layer usable with the staplecartridge of FIG. 19;

FIG. 23 is a perspective view of a staple cartridge in accordance withat least one embodiment comprising a wavy deck surface;

FIG. 24 is a detail view of the deck surface of the staple cartridge ofFIG. 23;

FIG. 25 is a plan view of the staple cartridge of FIG. 23;

FIG. 26 is an elevational view of the staple cartridge of FIG. 23;

FIG. 26A is a perspective view of a layer usable with the staplecartridge of FIG. 23;

FIG. 27 is a cross-sectional view of the staple cartridge of FIG. 19taken along line 27-27 in FIG. 21;

FIG. 28 is a cross-sectional view of the staple cartridge of FIG. 23taken along line 28-28 in FIG. 25;

FIG. 29 is a cross-sectional view of the staple cartridge of FIG. 19taken along line 29-29 in FIG. 21;

FIG. 30 is a cross-sectional view of the staple cartridge of FIG. 23taken along line 30-30 in FIG. 25;

FIG. 31 is a detail view of the wavy deck surface of the cartridge ofFIG. 19;

FIG. 32 is a detail view of the wavy deck surface of the cartridge ofFIG. 23;

FIG. 33 is a perspective view of a staple cartridge in accordance withat least one embodiment comprising a cartridge body and a layer;

FIG. 34 is a perspective view of the staple cartridge of FIG. 33illustrating the layer slid relative to the cartridge body;

FIG. 35 is a perspective view of the staple cartridge of FIG. 33illustrating the layer lifted away from the cartridge body;

FIG. 36 is a partial perspective view of a layer in accordance with atleast one alternative embodiment; and

FIG. 37 is a partial perspective view of a layer in accordance with atleast one alternative embodiment.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate various embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

The Applicant of the present application also owns the U.S. PatentApplications identified below which are each herein incorporated byreference in their respective entirety:

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U.S. patent application Ser. No. 12/894,340, entitled SURGICAL STAPLECARTRIDGES SUPPORTING NON-LINEARLY ARRANGED STAPLES AND SURGICALSTAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS; now U.S. Pat.No. 8,899,463;

U.S. patent application Ser. No. 12/894,327, entitled JAW CLOSUREARRANGEMENTS FOR SURGICAL INSTRUMENTS; now U.S. Pat. No. 8,978,956;

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U.S. patent application Ser. No. 12/894,338, entitled IMPLANTABLEFASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT; now U.S. Pat. No.8,864,007;

U.S. patent application Ser. No. 12/894,369, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER; now U.S. PatentApplication Publication No. 2012/0080344;

U.S. patent application Ser. No. 12/894,312, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS; now U.S. Pat. No.8,925,782;

U.S. patent application Ser. No. 12/894,377, entitled SELECTIVELYORIENTABLE IMPLANTABLE FASTENER CARTRIDGE; now U.S. Pat. No. 8,393,514;

U.S. patent application Ser. No. 12/894,339, entitled SURGICAL STAPLINGINSTRUMENT WITH COMPACT ARTICULATION CONTROL ARRANGEMENT; now U.S. Pat.No. 8,840,003;

U.S. patent application Ser. No. 12/894,360, entitled SURGICAL STAPLINGINSTRUMENT WITH A VARIABLE STAPLE FORMING SYSTEM; now U.S. Patent No.9,113,862;

U.S. patent application Ser. No. 12/894,322, entitled SURGICAL STAPLINGINSTRUMENT WITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS; now U.S.Pat. No. 8,740,034;

U.S. patent application Ser. No. 12/894,350, entitled SURGICAL STAPLECARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES; now U.S. PatentApplication Publication No. 2012/0080478;

U.S. patent application Ser. No. 12/894,383, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS; now U.S. Patent No.8,752,699;

U.S. patent application Ser. No. 12/894,389, entitled COMPRESSIBLEFASTENER CARTRIDGE; now U.S. Pat. No. 8,740,037;

U.S. patent application Ser. No. 12/894,345, entitled FASTENERSSUPPORTED BY A FASTENER CARTRIDGE SUPPORT; now U.S. Patent No 8,783,542;

U.S. patent application Ser. No. 12/894,306, entitled COLLAPSIBLEFASTENER CARTRIDGE; now U.S. Pat. No. 9,044,227;

U.S. patent application Ser. No. 12/894,318, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS; now U.S.Pat. No. 8.814,024;

U.S. patent application Ser. No. 12/894,330, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX; now U.S. PatentNo. 8,757,465;

U.S. patent application Ser. No. 12/894,361, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX; now U.S. Pat. No. 8,529,600;

U.S. patent application Ser. No. 12/894,367, entitled FASTENINGINSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTIONMATRIX; now U.S. Pat. No. 9,033,203;

U.S. patent application Ser. No. 12/894,388, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND A COVER; now U.S. Patent No.8.474,677;

U.S. patent application Ser. No. 12/894,376, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF FASTENER CARTRIDGES; now U.S. Patent No.9.044,228;

U.S. patent application Ser. No. 13/097,865, entitled SURGICAL STAPLERANVIL COMPRISING A PLURALITY OF FORMING POCKETS; now U.S. Patent No.9,295,464;

U.S. patent application Ser. No. 13/097,936, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER; now U.S. Pat. No. 8,657,176;

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U.S Patent Application Serial No 13/097,856, entitled STAPLE CARTRIDGECOMPRISING STAPLES POSITIONED WITHIN A COMPRESSIBLE PORTION THEREOF; nowU.S. Patent Application Publication No. 2012/0080336;

U.S. patent application Ser. No. 13/097,928, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING DETACHABLE PORTIONS; now U.S. Patent No.8.746,535;

U.S. patent application Ser. No. 13/097,891, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER COMPRISING AN ADJUSTABLE ANVIL; nowU.S. Pat. No. 8,864,009;

U.S. patent application Ser. No. 13/097,948, entitled STAPLE CARTRIDGECOMPRISING AN ADJUSTABLE DISTAL PORTION; now U.S. Pat. No. 8,978,954;

U.S. patent application Ser. No. 13/097,907, entitled COMPRESSIBLESTAPLE CARTRIDGE ASSEMBLY; now U.S. Pat. No. 9.301,755;

U.S. patent application Ser. No. 13/097,861, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES; now U.S.Pat. No. 9.113,865;

U.S. patent application Ser. No. 13/097,869, entitled STAPLE CARTRIDGELOADING ASSEMBLY; now U.S. Pat. No. 8,857,694;

U.S. patent application Ser. No. 13/097,917, entitled COMPRESSIBLESTAPLE CARTRIDGE COMPRISING ALIGNMENT MEMBERS; now U.S. Patent No.8.777,004;

U.S. patent application Ser. No. 13/097,873, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE PORTION; now U.S. Pat. No. 8,740,038;

U.S. patent application Ser. No. 13/097,938, entitled STAPLE CARTRIDGECOMPRISING COMPRESSIBLE DISTORTION RESISTANT COMPONENTS; now U.S. Pat.No. 9,016,542;

U.S. patent application Ser. No. 13/097,924, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR; now U.S. Patent No 9,168,038;

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U.S. patent application Ser. No. 13/242,086, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK; now U.S. Pat. No. 9,055,941;

U.S. patent application Ser. No. 13/241,912, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK ARRANGEMENT; now U.S. Pat. No. 9,050,084;

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U.S. patent application Ser. No. 13/241,637, entitled SURGICALINSTRUMENT WITH TRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATIONMOTIONS; now U.S. Pat. No. 8,789,741;

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U.S. patent application Ser. No. 13/433,103, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF LAYERS; now U.S. Pat. No.9,433,419;

U.S. patent application Ser. No. 13/433,098, entitled EXPANDABLE TISSUETHICKNESS COMPENSATOR; now U.S. Pat. No. 9,301,753;

U.S. patent application Ser. No. 13/433,102, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A RESERVOIR; now U.S. Pat. No. 9,232,941;

U.S. patent application Ser. No. 13/433,114, entitled RETAINER ASSEMBLYINCLUDING A TISSUE THICKNESS COMPENSATOR; now U.S. Pat. No. 9.386,988;

U.S. patent application Ser. No. 13/433,136, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT; now U.S. Pat. No.9,839,420;

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U.S. patent application Ser. No. 13/433,144, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD; now U.S. Pat.No. 9,277,919;

U.S. patent application Ser. No. 13/433,148, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING STRUCTURE TO PRODUCE A RESILIENT LOAD; now U.S.Pat. No. 9,220,500;

U.S. patent application Ser. No. 13/433,155, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING RESILIENT MEMBERS; now U.S. Pat. No. 9,480,476;

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U.S. patent application Ser. No. 13/433,167, entitled TISSUE THICKNESSCOMPENSATORS; now U.S. Pat. No. 9,220,501;

U.S. patent application Ser. No. 13/433,175, entitled LAYERED TISSUETHICKNESS COMPENSATOR; now U.S. Pat. No. 9,332,974;

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U.S. patent application Ser. No. 13/763,078, entitled ANVIL LAYERATTACHED TO A PROXIMAL END OF AN END EFFECTOR; now U.S. Patent No.9,848,875;

U.S. patent application Ser. No. 13/763,094, entitled LAYER COMPRISINGDEPLOYABLE ATTACHMENT MEMBERS; now U.S. Pat. No. 9,788,834;

U.S. patent application Ser. No. 13/763,106, entitled END EFFECTORCOMPRISING A DISTAL TISSUE ABUTMENT MEMBER; now U.S. Pat. No. 9,592,050;

U.S. patent application Ser. No. 13/433,147, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CHANNELS; now U.S. Pat. No. 9,351,730;

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U.S. patent application Ser. No. 13/763,035, entitled ACTUATOR FORRELEASING A TISSUE THICKNESS COMPENSATOR FROM A FASTENER CARTRIDGE; nowU.S. Pat. No. 10,213,198;

U.S. patent application Ser. No. 13/763,042, entitled RELEASABLE TISSUETHICKNESS COMPENSATOR AND FASTENER CARTRIDGE HAVING THE SAME; now U.S.Pat. No. 9,861,361;

U.S. patent application Ser. No. 13/763,048, entitled FASTENER CARTRIDGECOMPRISING A RELEASABLE TISSUE THICKNESS COMPENSATOR; now U.S. Pat. No.9,700,317;

U.S. patent application Ser. No. 13/763,054, entitled FASTENER CARTRIDGECOMPRISING A CUTTING MEMBER FOR RELEASING A TISSUE THICKNESSCOMPENSATOR; now U.S. Pat. No. 9,272,406;

U.S. patent application Ser. No. 13/763,065, entitled FASTENER CARTRIDGECOMPRISING A RELEASABLY ATTACHED TISSUE THICKNESS COMPENSATOR; now U.S.Pat. No. 9,566,061;

U.S. patent application Ser. No. 13/763,021, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE COVER; now U.S. Pat. No. 9,386,984;

U.S. patent application Ser. No. 13/763,078, entitled ANVIL LAYERATTACHED TO A PROXIMAL END OF AN END EFFECTOR; now U.S. Pat. No.9,848,875;

U.S. patent application Ser. No. 13/763,095, entitled LAYER ARRANGEMENTSFOR SURGICAL STAPLE CARTRIDGES; now U.S. Pat. No. 9,770,245;

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U.S. patent application Ser. No. 13/763,161, entitled RELEASABLE LAYEROF MATERIAL AND SURGICAL END EFFECTOR HAVING THE SAME; now U.S. PatentApplication Publication No. 2013/0153641;

U.S. patent application Ser. No. 13/763,177, entitled ACTUATOR FORRELEASING A LAYER OF MATERIAL FROM A SURGICAL END EFFECTOR; now U.S.Pat. No. 9,585,657;

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U.S. patent application Ser. No. 13/433,126, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING TISSUE INGROWTH FEATURES; now U.S. Pat. No.9,320,523;

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U.S. patent application Ser. No. 13/851,703, entitled FASTENER CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR INCLUDING OPENINGS THEREIN;now U.S. Pat. No. 9,572,577;

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U.S. patent application Ser. No. 13/851,684, entitled FASTENER CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR AND A GAP SETTING ELEMENT; nowU.S. Pat. No. 9,795,384;

U.S. patent application Ser. No. 14/187,387, entitled STAPLE CARTRIDGEINCLUDING A BARBED STAPLE; now U.S. Patent Application Publication No2014/0166724;

U.S. patent application Ser. No. 14/187,395, entitled STAPLE CARTRIDGEINCLUDING A BARBED STAPLE; now U.S. Patent Application Publication No2014/0166725;

U.S. patent application Ser. No. 14/187,400, entitled STAPLE CARTRIDGEINCLUDING A BARBED STAPLE; now U.S. Patent Application Publication No2014/0166726;

U.S. patent application Ser. No. 14/187,383, entitled IMPLANTABLE LAYERSAND METHODS FOR ALTERING IMPLANTABLE LAYERS FOR USE WITH SURGICALFASTENING INSTRUMENTS; now U.S. Pat. No. 9,839,422;

U.S. patent application Ser. No. 14/187,386, entitled IMPLANTABLE LAYERSAND METHODS FOR ALTERING ONE OR MORE PROPERTIES OF IMPLANTABLE LAYERSFOR USE WITH FASTENING INSTRUMENTS; now U.S. Pat. No 9.884,456;

U.S. patent application Ser. No. 14/187,390, entitled IMPLANTABLE LAYERSAND METHODS FOR MODIFYING THE SHAPE OF THE IMPLANTABLE LAYERS FOR USEWITH A SURGICAL FASTENING INSTRUMENT; now U.S. Pat. No. 9,839,423;

U.S. patent application Ser. No. 14/187,389, entitled IMPLANTABLE LAYERASSEMBLIES; now U.S. Pat. No. 9,757,124;

U.S. patent application Ser. No. 14/187,385, entitled IMPLANTABLE LAYERSCOMPRISING A PRESSED REGION; now U.S. Pat. No. 9,693,777; and

U.S. patent application Ser. No. 14/187,384, entitled FASTENING SYSTEMCOMPRISING A FIRING MEMBER LOCKOUT; now U.S. Pat. No. 9,775,608.

Numerous specific details are set forth to provide a thoroughunderstanding of the overall structure, function, manufacture, and useof the embodiments as described in the specification and illustrated inthe accompanying drawings. It will be understood by those skilled in theart, however, that the embodiments may be practiced without suchspecific details. In other instances, well-known operations, components,and elements have not been described in detail so as not to obscure theembodiments described in the specification. Those of ordinary skill inthe art will understand that the embodiments described and illustratedherein are non-limiting examples, and thus it can be appreciated thatthe specific structural and functional details disclosed herein may berepresentative and illustrative. Variations and changes thereto may bemade without departing from the scope of the claims.

The terms “comprise” (and any form of comprise, such as “comprises” and“comprising”), “have” (and any form of have, such as “has” and“having”), “include” (and any form of include, such as “includes” and“including”) and “contain” (and any form of contain, such as “contains”and “containing”) are open-ended linking verbs. As a result, a surgicalsystem, device, or apparatus that “comprises,” “has,” “includes” or“contains” one or more elements possesses those one or more elements,but is not limited to possessing only those one or more elements.Likewise, an element of a system, device, or apparatus that “comprises,”“has,” “includes” or “contains” one or more features possesses those oneor more features, but is not limited to possessing only those one ormore features.

The terms “proximal” and “distal” are used herein with reference to aclinician manipulating the handle portion of the surgical instrument.The term “proximal” referring to the portion closest to the clinicianand the term “distal” referring to the portion located away from theclinician. It will be further appreciated that, for convenience andclarity, spatial terms such as “vertical”, “horizontal”, “up”, and“down” may be used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and/or absolute.

Various exemplary devices and methods are provided for performinglaparoscopic and minimally invasive surgical procedures. However, theperson of ordinary skill in the art will readily appreciate that thevarious methods and devices disclosed herein can be used in numeroussurgical procedures and applications including, for example, inconnection with open surgical procedures. As the present DetailedDescription proceeds, those of ordinary skill in the art will furtherappreciate that the various instruments disclosed herein can be insertedinto a body in any way, such as through a natural orifice, through anincision or puncture hole formed in tissue, etc. The working portions orend effector portions of the instruments can be inserted directly into apatient's body or can be inserted through an access device that has aworking channel through which the end effector and elongated shaft of asurgical instrument can be advanced.

Many of the above-listed patent applications disclose various layerswhich are used in connection with a staple cartridge. When staples aredeployed from the staple cartridge, the staples can capture at least onelayer and implant the layer, or layers, against the tissue. Providedbelow is a brief description of a surgical stapling system. The staplecartridges and the layers disclosed herein can be used with thissurgical stapling system and/or any suitable stapling system.

A surgical stapling system can comprise a shaft and an end effectorextending from the shaft. The end effector comprises a first jaw and asecond jaw. The first jaw comprises a staple cartridge. The staplecartridge is insertable into and removable from the first jaw; however,other embodiments are envisioned in which a staple cartridge is notremovable from, or at least readily replaceable from, the first jaw. Thesecond jaw comprises an anvil configured to deform staples ejected fromthe staple cartridge. The second jaw is pivotable relative to the firstjaw about a closure axis; however, other embodiments are envisioned inwhich first jaw is pivotable relative to the second jaw. The surgicalstapling system further comprises an articulation joint configured topermit the end effector to be rotated, or articulated, relative to theshaft. The end effector is rotatable about an articulation axisextending through the articulation joint. Other embodiments areenvisioned which do not include an articulation joint.

The staple cartridge comprises a cartridge body. The cartridge bodyincludes a proximal end, a distal end, and a deck extending between theproximal end and the distal end. In use, the staple cartridge ispositioned on a first side of the tissue to be stapled and the anvil ispositioned on a second side of the tissue. The anvil is moved toward thestaple cartridge to compress and clamp the tissue against the deck.Thereafter, staples removably stored in the cartridge body can bedeployed into the tissue. The cartridge body includes staple cavitiesdefined therein wherein staples are removably stored in the staplecavities. The staple cavities are arranged in six longitudinal rows.Three rows of staple cavities are positioned on a first side of alongitudinal slot and three rows of staple cavities are positioned on asecond side of the longitudinal slot. Other arrangements of staplecavities and staples may be possible.

The staples are supported by staple drivers in the cartridge body. Thedrivers are movable between a first, or unfired position, and a second,or fired, position to eject the staples from the staple cavities. Thedrivers are retained in the cartridge body by a retainer which extendsaround the bottom of the cartridge body and includes resilient membersconfigured to grip the cartridge body and hold the retainer to thecartridge body. The drivers are movable between their unfired positionsand their fired positions by a sled. The sled is movable between aproximal position adjacent the proximal end and a distal positionadjacent the distal end. The sled comprises a plurality of rampedsurfaces configured to slide under the drivers and lift the drivers, andthe staples supported thereon, toward the anvil.

Further to the above, the sled is moved distally by a firing member. Thefiring member is configured to contact the sled and push the sled towardthe distal end. The longitudinal slot defined in the cartridge body isconfigured to receive the firing member. The anvil also includes a slotconfigured to receive the firing member. The firing member furthercomprises a first cam which engages the first jaw and a second cam whichengages the second jaw. As the firing member is advanced distally, thefirst cam and the second cam can control the distance, or tissue gap,between the deck of the staple cartridge and the anvil. The firingmember also comprises a knife configured to incise the tissue capturedintermediate the staple cartridge and the anvil. It is desirable for theknife to be positioned at least partially proximal to the rampedsurfaces such that the staples are ejected ahead of the knife.

A staple cartridge assembly 1000 is depicted in FIGS. 1-6A. The staplecartridge assembly 1000 comprises a cartridge body 1010 and a layer 1020(FIG. 6A). The cartridge body 1010 comprises a proximal end 1011 and adistal end 1012. The cartridge body 1010 further comprises alongitudinal slot 1013 defined therein which is configured to receive atleast a portion of a firing member therein. The slot 1013 extends fromthe proximal end 1011 toward the distal end 1012. The cartridge body1010 further comprises a plurality of staple cavities defined therein.The staple cavities are arranged in three longitudinal rows on a firstside of the longitudinal slot 1013 and three longitudinal rows on asecond side of the longitudinal slot 1013. On each side of thelongitudinal slot 1013, a first longitudinal row of staple cavities 1015a extends alongside the longitudinal slot 1013, a second row of staplecavities 1015 b extends alongside the first row of staple cavities 1015a, and a third row of staple cavities 1015 c extends alongside thesecond row of staple cavities 1015 c. The first row of staple cavities1015 a, the second row of staple cavities 1015 b, and the third row ofstaple cavities 1015 c are parallel to one another and the longitudinalslot 1013; however, embodiments are envisioned in which the first row ofstaple cavities 1015 a, the second row of staple cavities 1015 b, and/orthe third row of staple cavities 1015 c are not parallel to one anotherand/or the longitudinal slot 1013. Further to the above, the firingmember can be configured to lift staple drivers positioned within thecartridge body 1010 to eject staples removably stored in the staplecavities 1015 a, 1015 b, and 1015 c as the firing member is moved towardthe distal end 1012 of the staple cartridge 1000.

The staple cartridge body 1010 further comprises a tissue-supportingdeck 1014. The deck 1014 comprises a stepped surface. The deck 1014comprises a first step 1014 a adjacent the longitudinal slot 1013, asecond step 1014 b adjacent the first step 1014 a, and a third step 1014c adjacent the second step 1014 b on each side of the longitudinal slot1013. The first step 1014 a comprises a first plateau having a firstheight, the second step 1014 b comprises a second plateau having asecond height, and the third step 1014 c comprises a third plateauhaving a third height. The first plateau and the third plateau have thesame height. The first plateau and the third plateau are taller than thesecond plateau. Other embodiments are envisioned in which the firststep, the second step, and the third step have any suitable height.

Further to the above, the second step 1014 b of the deck 1014 isrecessed with respect to the first step 1014 a and the third step 1014c. The second step 1014 b comprises a longitudinal depression, or well,1019 b extending between the first step 1014 a and the third step 1014c. The longitudinal depression 1019 b extends between the proximal end1011 and the distal end 1012 of the cartridge body 1010. The secondstaple cavities 1015 b are positioned within the longitudinal depression1019 b. The longitudinal depression 1019 b is bounded by an innerlateral wall 1016 a, an outer lateral wall 1016 c, a proximal wall 1017,and a distal wall 1018. The proximal wall 1017 is positioned proximallywith respect to the staple cavities 1015 a, 1015 b, and 1015 c. Thedistal wall 1018 is positioned distally with respect to the staplecavities 1015 a, 1015 b, and 1015 c. The inner wall 1016 a transects thefirst staple cavities 1015 a. The inner wall 1016 a is at leastpartially comprised by the sidewalls of the first staple cavities 1015a. The deck 1014 surrounding the first staple cavities 1015 a extendsalong the first step 1014 a and the second step 1014 b. The outer wall1016 c transects the third staple cavities 1015 c. The outer wall 1016 cis at least partially comprised by the sidewalls of the third staplecavities 1015 c. The deck 1014 surrounding the third staple cavities1015 c extends along the third step 1014 c and the second step 1014 b.

The staple cartridge 1000 can be utilized with any suitable layer thatcan be implanted against the tissue being stapled. The layer cancomprise an adjunct material which is positioned on the deck 1014 of thecartridge body 1010 before the staple cartridge 1000 is inserted intothe patient. Such an adjunct material could comprise buttress materialand/or a tissue thickness compensator, for example. In variousinstances, the layer can move relative to the deck 1014 when the staplecartridge 1000 and the layer are positioned relative to the tissue thatis to be stapled.

Turning now to FIG. 6A, a layer 1020 comprises a bottom surface 1024configured to contact and be supported by the deck 1014 of the cartridgebody 1010. The layer 1020 further comprises longitudinal projections1029 extending therefrom which are configured to be received in thelongitudinal wells 1019 b. The projections 1029 can limit relativemotion between the layer 1020 and the cartridge body 1010. Theprojections 1029 are closely received between the inner wall 1016 a andthe outer wall 1016 c and, as a result, the projections 1029 can abutthe inner wall 1016 a and/or the outer wall 1016 c to limit lateraland/or longitudinal movement of the layer 1020. In various instances,each projection 1029 comprises a first lateral side wall 1026 aconfigured to engage the inner wall 1016 a and a second lateral sidewall 1026 b configured to engage the outer wall 1016 b. The projections1029 can be sized and configured such that they are compressed, orwedged, between the inner wall 1016 a and the outer wall 1016 c. Suchcompression, or wedging, can not only limit the lateral and longitudinalmovement of the layer 1020, it can also limit unintentional verticalmovement of the layer 1020 away from the deck 1014. As the reader willappreciate, the lateral compression, or wedging, is sufficient to holdthe layer 1020 in position yet, at the same, it can be overcome topermit the layer 1020 to be separated from the cartridge body 1010 afterthe staples have been fired and the layer 1020 has been implantedagainst the tissue.

In addition to or in lieu of the above, the projections 1029 can limitlongitudinal motion between the layer 1020 and the cartridge body 1010.The projections 1029 are closely received between the proximal wall 1017and the distal wall 1018 and, as a result, the projections 1029 can abutthe proximal wall 1017 and/or the distal wall 1018 to limit longitudinalmovement of the layer 1020. In various instances, each projection 1029comprises a proximal end wall 1027 configured to engage the proximalwall 1017 and a distal end wall 1028 configured to engage the distalwall 1018. The projections 1029 can be sized and configured such thatthey are compressed, or wedged, between the proximal wall 1017 and thedistal wall 1018. Such compression, or wedging, can not only limit thelongitudinal movement of the layer 1020, it can also limit unintentionalvertical movement of the layer 1020 away from the deck 1014. As thereader will appreciate, the longitudinal compression, or wedging, issufficient to hold the layer 1020 in position yet, at the same, it canbe overcome to permit the layer 1020 to be separated from the cartridgebody 1010 after the staples have been fired and the layer 1020 has beenimplanted against the tissue.

The projections 1029 comprise a negative impression of the voids createdby the wells 1019 b; however, the projections 1029 can comprise anysuitable configuration. The projections 1029 are defined by contourswhich cause the projections 1029 to fit snugly within the wells 1019 b.The projections 1029 can be larger than the wells 1019 b such that theprojections 1029 are compressed when they are positioned in the wells1019 b. Such an arrangement can generate a biasing and/or retentionforce between the layer 1020 and the cartridge body 1010.

Each staple cavity 1015 a, 1015 b, and 1015 c is configured to removablystore a staple therein. In various instances, the staples stored in thestaple cavities 1015 a, 1015 b, and 1015 c have the same unformedheight. The unformed height of a staple is the overall height of thestaple before it is deformed by an anvil. In certain instances, suchstaples can be deformed to the same formed height. In other instances,such staples can be deformed to different formed heights. For example,the staples ejected from the first staple cavities 1015 a can bedeformed to a first deformed height, the staples ejected from the secondstaple cavities 1015 b can be deformed to a second deformed height, andthe staples ejected from the third staple cavities 1015 c can bedeformed to a third deformed height. The first deformed height can beshorter than the second deformed height and the second deformed heightcan be shorter than the third deformed height. Such an arrangement canprovide a tissue compression gradient with respect to an incision madein the tissue. In various instances, the staples stored in the staplecavities 1015 a, 1015 b, and 1015 c can have different unformed heights.For example, the staples ejected from the first staple cavities 1015 acan have a first unformed height, the staples ejected from the secondstaple cavities 1015 b can have a second unformed height, and thestaples ejected from the third staple cavities 1015 c can have a thirdunformed height. The first unformed height can be shorter than thesecond unformed height and the second unformed height can be shorterthan the third unformed height. In various other instances, the secondunformed height can be shorter than the first unformed height and thethird unformed height. In at least one such instance, the first unformedheight and the third unformed height can be the same.

The disclosures of U.S. Pat. No. 7,866,528, entitled STAPLE DRIVEASSEMBLY, which issued on Jan. 1, 2011; U.S. Pat. No. 7,726,537,entitled SURGICAL STAPLER WITH UNIVERSAL ARTICULATION AND TISSUEPRE-CLAMP, which issued on Jun. 1, 2010; U.S. Pat. No. 7,641,091,entitled STAPLE DRIVE ASSEMBLY, which issued on Jan. 5, 2010; U.S. Pat.No. 7,635,074, entitled STAPLE DRIVE ASSEMBLY, which issued on Dec. 22,2009; and U.S. Pat. No. 7,997,469, entitled STAPLE DRIVE ASSEMBLY, whichissued on Aug. 16, 2011, are hereby incorporated by reference herein intheir respective entireties. The disclosure of U.S. Pat. No. 8,317,070,entitled SURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVINGDIFFERENT LENGTHS, which issued on Nov. 27, 2012, is incorporated byreference in its entirety.

Referring to FIGS. 1 and 6A, the layer 1020 comprises a longitudinalprotrusion 1023 configured to extend into the longitudinal slot 1013 ofthe cartridge body 1010. The protrusion 1023 can be sized and configuredsuch that it is wedged into and compressed within the slot 1013. Theprotrusion 1023 can be incised by the cutting portion of the firingmember as the firing member is advanced distally. Such an incision canfacilitate the release of the layer 1020 from the cartridge body 1010.

A staple cartridge assembly 1100 is depicted in FIGS. 7-12A. The staplecartridge assembly 1100 comprises a cartridge body 1110 and a layer 1120(FIG. 12A). The cartridge body 1110 comprises a proximal end 1111 and adistal end 1112. The cartridge body 1110 further comprises alongitudinal slot 1113 defined therein which is configured to receive atleast a portion of a firing member therein. The slot 1113 extends fromthe proximal end 1111 toward the distal end 1112. The cartridge body1110 further comprises a plurality of staple cavities defined therein.The staple cavities are arranged in three longitudinal rows on a firstside of the longitudinal slot 1113 and three longitudinal rows on asecond side of the longitudinal slot 1113. On each side of thelongitudinal slot 1113, a first longitudinal row of staple cavities 1115a extends alongside the longitudinal slot 1113, a second row of staplecavities 1115 b extends alongside the first row of staple cavities 1115a, and a third row of staple cavities 1115 c extends alongside thesecond row of staple cavities 1115 b. The first row of staple cavities1115 a, the second row of staple cavities 1115 b, and the third row ofstaple cavities 1115 c are parallel to one another and the longitudinalslot 1113; however, embodiments are envisioned in which the first row ofstaple cavities 1115 a, the second row of staple cavities 1115 b, and/orthe third row of staple cavities 1115 c are not parallel to one anotherand/or the longitudinal slot 1113. Further to the above, the firingmember can be configured to lift staple drivers positioned within thecartridge body 1110 to eject staples removably stored in the staplecavities 1115 a, 1115 b, and 1115 c as the firing member is moved towardthe distal end 1112 of the staple cartridge 1100.

The first staple cavities 1115 a are positioned at regular intervalsalong a first longitudinal axis. Spaces between adjacent first staplecavities 1115 a can be referred to as staple gaps in the firstlongitudinal row as tissue positioned over such spaces will not bestapled by staples ejected from the first staple cavities 1115 a. Thesecond staple cavities 1115 b are also positioned at regular intervalsalong a second longitudinal axis. The second staple cavities 1115 b arestaggered with respect to the first staple cavities 1115 a. The secondstaple cavities 1115 b are positioned laterally with respect to thestaple gaps in the first row of staple cavities 1115 a. Spaces betweenadjacent second staple cavities 1115 b can also be referred to as staplegaps in the second longitudinal row as tissue positioned over suchspaces will not be stapled by staples ejected from the second staplecavities 1115 b. The third staple cavities 1115 c are also positioned atregular intervals along a third longitudinal axis. The third staplecavities 1115 c are staggered with respect to the second staple cavities1115 b. The third staple cavities 1115 c are positioned laterally withrespect to the staple gaps in the second row of staple cavities 1115 b.

The staple cartridge body 1110 further comprises a tissue-supportingdeck 1114. The deck 1114 comprises a stepped surface. The deck 1114comprises a first step 1114 a adjacent the longitudinal slot 1113, asecond step 1114 b adjacent the first step 1114 a, and a third step 1114c adjacent the second step 1114 b. The deck 1114 comprises a first step1114 a, a second step 1114 b, and a third step 1114 c on each side ofthe longitudinal slot 1113. The first step 1114 a comprises a firstplateau having a first height, the second step 1114 b comprises aplurality of walls having a second height, and the third step 1114 ccomprises a third plateau having a third height. The plurality of wallscan collectively define a second plateau. The first plateau and thesecond plateau have the same height. The first plateau and the secondplateau are taller than the third plateau. Other embodiments areenvisioned in which the first step, the second step, and the third stephave any suitable height.

Further to the above, the walls of the second step 1114 b extendoutwardly, or laterally, from the first step 1114 a. The walls of thesecond step 1114 b are connected to the first step 1114 a; however,embodiments are envisioned in which the walls are not connected to thefirst step 1114 a. Each wall extends around an end of a first staplecavity 1115 a, a second staple cavity 1115 b, and/or a third staplecavity 1115 c. Owing to the staggered arrangement of the staple cavities1115 a, 1115 b, and 1115 c, discussed above, each wall weaves throughthe first row of staple cavities 1115 a, the second row of staplecavities 1115 b, and/or the third row of staple cavities 1115 c. Eachwall can comprise straight sections and/or curved sections. In variousinstances, the curved sections extend around the ends of the staplecavities while the straight sections extend between the rows of staplecavities.

The deck 1114 comprises a plurality of depressions, or wells, 1119. Thewells 1119 are defined by the first step 1114 a, the walls of the secondstep 1114 b, a proximal wall 1117, and/or a distal wall 1118. The wells1119 are not completely enclosed. Each well 1119 is bounded on threesides, i.e., a proximal side, a distal side, and an inner side. Theouter side is unbounded, or at least substantially unbounded; however,other embodiments are envisioned in which the wells are bounded on lessthan three sides. Certain other embodiments are envisioned in which thewells are completely bounded. Each well 1119 comprises a bottom 1119 b.The bottoms 1119 b of the wells 1119 have the same height as the thirdstep 1114 c; however, other embodiments are envisioned in which the wellbottoms 1119 b have a different height than the third step 1114 c.

The staple cartridge 1100 can be utilized with any suitable layer thatcan be implanted against the tissue being stapled. The layer cancomprise an adjunct material which is positioned on the deck 1114 of thecartridge body 1110 before the staple cartridge 1100 is inserted intothe patient. Such an adjunct material could comprise buttress materialand/or a tissue thickness compensator, for example. In variousinstances, the layer can move relative to the deck 1114 when the staplecartridge 1100 and the layer are positioned relative to the tissue thatis to be stapled.

Turning now to FIG. 12A, a layer 1120 comprises a bottom surface 1124configured to contact and be supported by the deck 1114 of the cartridgebody 1110. The layer 1120 further comprises slits 1124 b which areconfigured to receive the walls of the second step 1114 b. Theinteraction between the slits 1124 b and the walls can limit relativemotion between the layer 1120 and the cartridge body 1110. The walls ofthe second step 1114 b are closely received in the slits 1124 b and, asa result, the side walls of the slits 1124 b can abut and/or grip thesidewalls of the walls of the second step 1114 b to limit lateralmovement of the layer 1120. Such an arrangement can generate a biasingand/or retention force between the layer 1120 and the cartridge body1110. The walls of the second step 1114 b can be sized and configuredsuch that they are compressed, or wedged, within the slits 1124 b. Suchcompression, or wedging, can not only limit the lateral and longitudinalmovement of the layer 1120, it can also limit unintentional verticalmovement of the layer 1120 away from the deck 1114. As the reader willappreciate, the lateral and longitudinal compression, or wedging, issufficient to hold the layer 1120 in position yet, at the same, it canbe overcome to permit the layer 1120 to be separated from the cartridgebody 1110 after the staples have been fired and the layer 1120 has beenimplanted against the tissue.

The layer 1120 is closely received between the proximal wall 1117 andthe distal wall 1118 and, as a result, the layer 1120 can abut theproximal wall 1117 and/or the distal wall 1118 to limit longitudinalmovement of the layer 1120. The layer 1120 comprises a proximal end wall1127 configured to engage the proximal wall 1117 and a distal end wall1128 configured to engage the distal wall 1118. The layer 1120 can besized and configured such that it is compressed, or wedged, between theproximal wall 1117 and the distal wall 1118. Such compression, orwedging, can not only limit the longitudinal movement of the layer 1120,it can also limit unintentional vertical movement of the layer 1120 awayfrom the deck 1114. As the reader will appreciate, the longitudinalcompression, or wedging, is sufficient to hold the layer 1120 inposition yet, at the same, it can be overcome to permit the layer 1120to be separated from the cartridge body 1110 after the staples have beenfired and the layer 1120 has been implanted against the tissue.

Each staple cavity 1115 a, 1115 b, and 1115 c is configured to removablystore a staple therein. In various instances, the staples stored in thestaple cavities 1115 a, 1115 b, and 1115 c have the same unformedheight. In certain instances, such staples can be deformed to the sameformed height. In other instances, such staples can be deformed todifferent formed heights. For example, the staples ejected from thefirst staple cavities 1115 a can be deformed to a first deformed height,the staples ejected from the second staple cavities 1115 b can bedeformed to a second deformed height, and the staples ejected from thethird staple cavities 1115 c can be deformed to a third deformed height.The first deformed height can be shorter than the second deformed heightand the second deformed height can be shorter than the third deformedheight. Such an arrangement can provide a tissue compression gradientwith respect to an incision made in the tissue. In various instances,the staples stored in the staple cavities 1115 a, 1115 b, and 1115 c canhave different unformed heights. For example, the staples ejected fromthe first staple cavities 1115 a can have a first unformed height, thestaples ejected from the second staple cavities 1115 b can have a secondunformed height, and the staples ejected from the third staple cavities1115 c can have a third unformed height. The first unformed height canbe shorter than the second unformed height and the second unformedheight can be shorter than the third unformed height. In various otherinstances, the second unformed height can be shorter than the firstunformed height. In at least one instance, the second unformed heightand the third unformed height can be the same.

In various instances, the walls of the second step 1114 a can beconfigured to guide the staples as the staples are ejected from thestaple cavities 1115 a, 1115 b, and/or 1115 c. In certain instances, thewalls of the second step 1114 a can extend the staple cavities 1115 a,1115 b, and/or 1115 c to control the staples stored therein as they arebeing ejected.

Referring to FIGS. 7 and 12A, the layer 1120 comprises a longitudinalprotrusion 1123 configured to extend into the longitudinal slot 1113 ofthe cartridge body 1110. The protrusion 1123 can be sized and configuredsuch that it is wedged into and compressed within the slot 1113. Theprotrusion 1123 can be incised by the cutting portion of the firingmember as the firing member is advanced distally. Such an incision canfacilitate the release of the layer 1120 from the cartridge body 1110.

A staple cartridge assembly 1200 is depicted in FIGS. 13-18A. The staplecartridge assembly 1200 comprises a cartridge body 1210 and a layer 1220(FIG. 18A). The cartridge body 1210 comprises a proximal end 1211 and adistal end 1212. The cartridge body 1210 further comprises alongitudinal slot 1213 defined therein which is configured to receive atleast a portion of a firing member therein. The slot 1213 extends fromthe proximal end 1211 toward the distal end 1212. The cartridge body1210 further comprises a plurality of staple cavities defined therein.The staple cavities are arranged in three longitudinal rows on a firstside of the longitudinal slot 1213 and three longitudinal rows on asecond side of the longitudinal slot 1213. On each side of thelongitudinal slot 1213, a first longitudinal row of staple cavities 1215a extends alongside the longitudinal slot 1213, a second row of staplecavities 1215 b extends alongside the first row of staple cavities 1215a, and a third row of staple cavities 1215 c extends alongside thesecond row of staple cavities 1215 b. The first row of staple cavities1215 a, the second row of staple cavities 1215 b, and the third row ofstaple cavities 1215 c are parallel to one another and the longitudinalslot 1213; however, embodiments are envisioned in which the first row ofstaple cavities 1215 a, the second row of staple cavities 1215 b, and/orthe third row of staple cavities 1215 c are not parallel to one anotherand/or the longitudinal slot 1213. Further to the above, the firingmember can be configured to lift staple drivers positioned within thecartridge body 1210 to eject staples removably stored in the staplecavities 1215 a, 1215 b, and 1215 c as the firing member is moved towardthe distal end 1212 of the staple cartridge 1200.

The first staple cavities 1215 a are positioned at regular intervalsalong a first longitudinal axis. Spaces between adjacent first staplecavities 1215 a can be referred to as staple gaps in the firstlongitudinal row as tissue positioned over such spaces will not bestapled by staples ejected from the first staple cavities 1215 a. Thesecond staple cavities 1215 b are also positioned at regular intervalsalong a second longitudinal axis. The second staple cavities 1215 b arestaggered with respect to the first staple cavities 1215 a. The secondstaple cavities 1215 b are positioned laterally with respect to thestaple gaps in the first row of staple cavities 1215 a. Spaces betweenadjacent second staple cavities 1215 b can also be referred to as staplegaps in the second longitudinal row as tissue positioned over suchspaces will not be stapled by staples ejected from the second staplecavities 1215 b. The third staple cavities 1215 c are also positioned atregular intervals along a third longitudinal axis. The third staplecavities 1215 c are staggered with respect to the second staple cavities1215 b. The third staple cavities 1215 c are positioned laterally withrespect to the staple gaps in the second row of staple cavities 1215 b.

The staple cartridge body 1210 further comprises a tissue-supportingdeck 1214. The deck 1214 comprises a plurality of depressions, or wells,defined therein. A first well 1219 a surrounds each first staple cavity1215 a. Each first well 1219 a is defined by a substantially triangularwall 1216 a comprising a vertex pointing proximally, a vertex pointingdistally, and a vertex pointing laterally outwardly. Each first well1219 a comprises a first floor 1214 a which is a first depth from thedeck 1214. A second well 1219 b surrounds each second staple cavity 1215b. Each second well 1219 b is defined by a wall 1216 b which issubstantially diamond-shaped comprising a vertex pointing proximally, avertex pointing distally, a vertex pointing laterally inwardly, and avertex pointing laterally outwardly. Each second well 1219 b comprises asecond floor 1214 b which is a second depth from the deck 1214. A thirdwell 1219 c surrounds each third staple cavity 1215 c. Each third well1219 c is defined by a substantially triangular wall 1216 c comprising avertex pointing proximally, a vertex pointing distally, and a vertexpointing laterally inwardly. Each third well 1219 c comprises a thirdfloor 1214 c which is a third depth from the deck 1214.

The first wells 1219 a are positioned at regular intervals along a firstlongitudinal axis. Gaps are present between adjacent first wells 1219 a.The second wells 1219 b are also positioned at regular intervals along asecond longitudinal axis. The second wells 1219 b are staggered withrespect to the first wells 1219 b. The second wells 1219 b arepositioned laterally with respect to the gaps in the first row of wells1219 a. Gaps are present between adjacent second wells 1219 b. The thirdwells 1219 c are also positioned at regular intervals along a thirdlongitudinal axis. The third wells 1219 c are staggered with respect tothe second wells 1219 b. The third wells 1219 c are positioned laterallywith respect to the gaps in the second row of wells 1219 b.

Further to the above, the first depth of the first wells 1219 a, thesecond depth of the second wells 1219 b, and the third depth of thethird wells 1219 c can have the same depth. In other instances, thefirst depth, the second depth, and/or the third depth can be different.

The staple cartridge 1200 can be utilized with any suitable layer thatcan be implanted against the tissue being stapled. The layer cancomprise an adjunct material which is positioned on the deck 1214 of thecartridge body 1210 before the staple cartridge 1200 is inserted intothe patient. Such an adjunct material could comprise buttress materialand/or a tissue thickness compensator, for example. In variousinstances, the layer can move relative to the deck 1214 when the staplecartridge 1200 and the layer are positioned relative to the tissue thatis to be stapled.

Turning now to FIG. 18A, a layer 1220 comprises a bottom surface 1224configured to contact and be supported by the deck 1214 of the cartridgebody 1210. The layer 1220 further comprises projections 1229 a, 1229 b,and 1229 c extending therefrom which are configured to be received inthe wells 1219 a, 1219 b, and 1219 c, respectively. The projections 1229a, 1229 b, and 1229 c can limit relative motion between the layer 1220and the cartridge body 1210. The projections 1229 a, 1229 b, and 1229 care closely received in the wells 1219 a, 1219 b, and 1219 c,respectively, and, as a result, the projections 1229 a, 1229 b, and 1229c can abut the sidewalls of the wells 1219 a, 1219 b, and 1219 c tolimit lateral and longitudinal movement of the layer 1220. Theprojections 1229 a, 1229 b, and 1229 c can be sized and configured suchthat they are compressed, or wedged, within the wells 1219 a, 1219 b,and 1219 c, respectively. Such compression, or wedging, can not onlylimit the lateral and longitudinal movement of the layer 1220, it canalso limit unintentional vertical movement of the layer 1220 away fromthe deck 1214. As the reader will appreciate, the lateral andlongitudinal compression, or wedging, is sufficient to hold the layer1220 in position yet, at the same, it can be overcome to permit thelayer 1220 to be separated from the cartridge body 1210 after thestaples have been fired and the layer 1220 has been implanted againstthe tissue.

The layer 1220 is closely received between a proximal wall 1217 and adistal wall 1218 and, as a result, the layer 1220 can abut the proximalwall 1217 and/or the distal wall 1218 to limit longitudinal movement ofthe layer 1220. The layer 1220 comprises a proximal end wall 1227configured to engage the proximal wall 1217 and a distal end wall 1228configured to engage the distal wall 1218. The layer 1220 can be sizedand configured such that it is compressed, or wedged, between theproximal wall 1217 and the distal wall 1218. Such compression, orwedging, can not only limit the longitudinal movement of the layer 1220,it can also limit unintentional vertical movement of the layer 1220 awayfrom the deck 1214. As the reader will appreciate, the longitudinalcompression, or wedging, is sufficient to hold the layer 1220 inposition yet, at the same, it can be overcome to permit the layer 1220to be separated from the cartridge body 1210 after the staples have beenfired and the layer 1220 has been implanted against the tissue.

The projections 1229 a, 1229 b, and 1229 c comprise a negativeimpression of the voids created by the wells 1219 a, 1219 b, and 1219 c,respectively; however, the projections 1229 a, 1229 b, and 1229 c cancomprise any suitable configuration. The projections 1229 a, 1229 b, and1229 c are defined by contours which cause the projections 1229 a, 1229b, and 1229 c to fit snugly within the wells 1219 a, 1219 b, and 1219 c,respectively. The projections 1229 a, 1229 b, and 1229 c can be largerthan the wells 1219 a, 1219 b, and 1219 c, respectively, such that theprojections 1229 a, 1229 b, and 1229 c are compressed when they arepositioned in the wells 1219 a, 1219 b, and 1219 c. Such an arrangementcan generate a biasing and/or retention force between the layer 1220 andthe cartridge body 1210.

Each staple cavity 1215 a, 1215 b, and 1215 c is configured to removablystore a staple therein. In various instances, the staples stored in thestaple cavities 1215 a, 1215 b, and 1215 c have the same unformedheight. In certain instances, such staples can be deformed to the sameformed height. In other instances, such staples can be deformed todifferent formed heights. For example, the staples ejected from thefirst staple cavities 1215 a can be deformed to a first deformed height,the staples ejected from the second staple cavities 1215 b can bedeformed to a second deformed height, and the staples ejected from thethird staple cavities 1215 c can be deformed to a third deformed height.The first deformed height can be shorter than the second deformed heightand the second deformed height can be shorter than the third deformedheight. Such an arrangement can provide a tissue compression gradientwith respect to an incision made in the tissue. In various instances,the staples stored in the staple cavities 1215 a, 1215 b, and 1215 c canhave different unformed heights. For example, the staples ejected fromthe first staple cavities 1215 a can have a first unformed height, thestaples ejected from the second staple cavities 1215 b can have a secondunformed height, and the staples ejected from the third staple cavities1215 c can have a third unformed height. The first unformed height canbe shorter than the second unformed height and the second unformedheight can be shorter than the third unformed height.

A staple cartridge assembly 1400 is depicted in FIGS. 23-26A, 28, 30,and 32. The staple cartridge assembly 1400 comprises a cartridge body1410 and a layer 1420 (FIG. 26A). The cartridge body 1410 comprises aproximal end 1411 and a distal end 1412. The cartridge body 1410 furthercomprises a longitudinal slot 1413 defined therein which is configuredto receive at least a portion of a firing member therein. The slot 1413extends from the proximal end 1411 toward the distal end 1412. Thecartridge body 1410 further comprises a plurality of staple cavitiesdefined therein. The staple cavities are arranged in three longitudinalrows on a first side of the longitudinal slot 1413 and threelongitudinal rows on a second side of the longitudinal slot 1413. Oneach side of the longitudinal slot 1413, a first longitudinal row ofstaple cavities 1415 a extends alongside the longitudinal slot 1413, asecond row of staple cavities 1415 b extends alongside the first row ofstaple cavities 1415 a, and a third row of staple cavities 1415 cextends alongside the second row of staple cavities 1415 b. The firstrow of staple cavities 1415 a, the second row of staple cavities 1415 b,and the third row of staple cavities 1415 c are parallel to one anotherand the longitudinal slot 1413; however, embodiments are envisioned inwhich the first row of staple cavities 1415 a, the second row of staplecavities 1415 b, and/or the third row of staple cavities 1415 c are notparallel to one another and/or the longitudinal slot 1413. Further tothe above, the firing member can be configured to lift staple driverspositioned within the cartridge body 1410 to eject staples removablystored in the staple cavities 1415 a, 1415 b, and 1415 c as the firingmember is moved toward the distal end 1412 of the staple cartridge 1400.

The first staple cavities 1415 a are positioned at regular intervalsalong a first longitudinal axis. Spaces between adjacent first staplecavities 1415 a can be referred to as staple gaps in the firstlongitudinal row as tissue positioned over such spaces will not bestapled by staples ejected from the first staple cavities 1415 a. Thesecond staple cavities 1415 b are also positioned at regular intervalsalong a second longitudinal axis. The second staple cavities 1415 b arestaggered with respect to the first staple cavities 1415 a. The secondstaple cavities 1415 b are positioned laterally with respect to thestaple gaps in the first row of staple cavities 1415 a. Spaces betweenadjacent second staple cavities 1415 b can also be referred to as staplegaps in the second longitudinal row as tissue positioned over suchspaces will not be stapled by staples ejected from the second staplecavities 1415 b. The third staple cavities 1415 c are also positioned atregular intervals along a third longitudinal axis. The third staplecavities 1415 c are staggered with respect to the second staple cavities1415 b. The third staple cavities 1415 c are positioned laterally withrespect to the staple gaps in the second row of staple cavities 1415 b.

The staple cartridge body 1410 further comprises a tissue-supportingdeck 1414. The deck 1414 comprises a plurality of peaks 1416 and valleys1419 defined therein. The valleys 1419 are aligned with the first staplecavities 1415 a, the second staple cavities 1415 b, and the third staplecavities 1415 c. The peaks 1416 are aligned with the gaps between thefirst staple cavities 1415 a. The peaks 1416 are also aligned with thegaps between the second staple cavities 1415 b. Similarly, the peaks1416 are aligned with the gaps between the third staple cavities 1415 c.The peaks 1416 in the first row of staple cavities 1415 a can beconnected to the peaks 1416 in the second row of staple cavities 1415 b.Similarly, the peaks 1416 in the second row of staple cavities 1415 bcan be connected to the peaks 1416 in the third row of staple cavities1415 c. The wells 1419 each have the same depth; however, otherembodiments are envisioned in which the wells have different depths. Forinstance, the wells aligned with the first staple cavities 1415 a canhave a first depth, the wells aligned with the second staple cavities1415 b can have a second depth, and the wells aligned with the thirdstaple cavities 1415 c can have a third depth, wherein the first depth,the second depth, and/or the third depth can be different. The peaks1416 each have the same height; however, other embodiments areenvisioned in which the peaks have different heights. For instance, thepeaks positioned between the first staple cavities 1415 a can have afirst height, the peaks positioned between the second staple cavities1415 b can have a second height, and the peaks positioned between thethird staple cavities 1415 c can have a third height, wherein the firstheight, the second height, and/or the third height can be different.

The staple cartridge 1400 can be utilized with any suitable layer thatcan be implanted against the tissue being stapled. The layer cancomprise an adjunct material which is positioned on the deck 1414 of thecartridge body 1410 before the staple cartridge 1400 is inserted intothe patient. Such an adjunct material could comprise buttress materialand/or a tissue thickness compensator, for example. In variousinstances, the layer can move relative to the deck 1414 when the staplecartridge 1400 and the layer are positioned relative to the tissue thatis to be stapled.

Turning now to FIG. 26A, a layer 1420 comprises a bottom surface 1424configured to contact and be supported by the deck 1414 of the cartridgebody 1410. The bottom surface 1424 comprises peaks 1429 extendingtherefrom which are configured to be received in the valleys 1419defined in the deck 1414. The peaks 1429 can limit relative motionbetween the layer 1420 and the cartridge body 1410. The peaks 1429 areclosely received within the valleys 1419 and, as a result, the peaks1429 can abut the walls of the valleys 1419 to limit lateral and/orlongitudinal movement of the layer 1420. The bottom surface 1424 furthercomprises valleys 1426 defined therein which are configured to receivepeaks 1416 extending from the cartridge body 1410. The valleys 1426 canlimit relative motion between the layer 1420 and the cartridge body1410. The peaks 1416 are closely received within the valleys 1426 and,as a result, the peaks 1416 can abut the walls of the valleys 1426 tolimit lateral and/or longitudinal movement of the layer 1420.

In addition to or in lieu of the above, the layer 1420 is closelyreceived between a proximal wall 1417 and a distal wall 1418 of thecartridge body 1410 and, as a result, the layer 1420 can abut theproximal wall 1417 and/or the distal wall 1418 to limit longitudinalmovement of the layer 1420. The layer 1420 comprises a proximal end wall1427 configured to engage the proximal wall 1417 and a distal end wall1428 configured to engage the distal wall 1418. The layer 1420 can besized and configured such that it is compressed, or wedged, between theproximal wall 1417 and the distal wall 1418. Such compression, orwedging, can not only limit the longitudinal movement of the layer 1420,it can also limit unintentional vertical movement of the layer 1420 awayfrom the deck 1414. The longitudinal compression, or wedging, issufficient to hold the layer 1420 in position yet, at the same, it canbe overcome to permit the layer 1420 to be separated from the cartridgebody 1410 after the staples have been fired and the layer 1420 has beenimplanted against the tissue.

The valleys 1426 and the peaks 1429 comprise a negative impression ofthe peaks 1416 and the valleys 1419, respectively; however, the layer1420 can comprise any suitable configuration. The valleys 1426 and thepeaks 1429 are defined by contours which cause the valleys 1426 and thepeaks 1429 to fit snugly within the peaks 1416 and the valleys 1419,respectively.

Each staple cavity 1415 a, 1415 b, and 1415 c is configured to removablystore a staple therein. In various instances, the staples stored in thestaple cavities 1415 a, 1415 b, and 1415 c have the same unformedheight. In certain instances, such staples can be deformed to the sameformed height. In other instances, such staples can be deformed todifferent formed heights. For example, the staples ejected from thefirst staple cavities 1415 a can be deformed to a first deformed height,the staples ejected from the second staple cavities 1415 b can bedeformed to a second deformed height, and the staples ejected from thethird staple cavities 1415 c can be deformed to a third deformed height.The first deformed height can be shorter than the second deformed heightand the second deformed height can be shorter than the third deformedheight. Such an arrangement can provide a tissue compression gradientwith respect to an incision made in the tissue. In various instances,the staples stored in the staple cavities 1415 a, 1415 b, and 1415 c canhave different unformed heights. For example, the staples ejected fromthe first staple cavities 1415 a can have a first unformed height, thestaples ejected from the second staple cavities 1415 b can have a secondunformed height, and the staples ejected from the third staple cavities1415 c can have a third unformed height. The first unformed height canbe shorter than the second unformed height and the second unformedheight can be shorter than the third unformed height.

A staple cartridge assembly 1300 is depicted in FIGS. 19-22A, 27, 29,and 31. The staple cartridge assembly 1300 comprises a cartridge body1310 and a layer 1320 (FIG. 22A). The cartridge body 1310 comprises aproximal end 1311 and a distal end 1312. The cartridge body 1310 furthercomprises a longitudinal slot 1313 defined therein which is configuredto receive at least a portion of a firing member therein. The slot 1313extends from the proximal end 1311 toward the distal end 1312. Thecartridge body 1310 further comprises a plurality of staple cavitiesdefined therein. The staple cavities are arranged in three longitudinalrows on a first side of the longitudinal slot 1313 and threelongitudinal rows on a second side of the longitudinal slot 1313. Oneach side of the longitudinal slot 1313, a first longitudinal row ofstaple cavities 1315 a extends alongside the longitudinal slot 1313, asecond row of staple cavities 1315 b extends alongside the first row ofstaple cavities 1315 a, and a third row of staple cavities 1315 cextends alongside the second row of staple cavities 1315 b. The firstrow of staple cavities 1315 a, the second row of staple cavities 1315 b,and the third row of staple cavities 1315 c are parallel to one anotherand the longitudinal slot 1313; however, embodiments are envisioned inwhich the first row of staple cavities 1315 a, the second row of staplecavities 1315 b, and/or the third row of staple cavities 1315 c are notparallel to one another and/or the longitudinal slot 1313. Further tothe above, the firing member can be configured to lift staple driverspositioned within the cartridge body 1310 to eject staples removablystored in the staple cavities 1315 a, 1315 b, and 1315 c as the firingmember is moved toward the distal end 1312 of the staple cartridge 1300.

The first staple cavities 1315 a are positioned at regular intervalsalong a first longitudinal axis. Spaces between adjacent first staplecavities 1315 a can be referred to as staple gaps in the firstlongitudinal row as tissue positioned over such spaces will not bestapled by staples ejected from the first staple cavities 1315 a. Thesecond staple cavities 1315 b are also positioned at regular intervalsalong a second longitudinal axis. The second staple cavities 1315 b arestaggered with respect to the first staple cavities 1315 a. The secondstaple cavities 1315 b are positioned laterally with respect to thestaple gaps in the first row of staple cavities 1315 a. Spaces betweenadjacent second staple cavities 1315 b can also be referred to as staplegaps in the second longitudinal row as tissue positioned over suchspaces will not be stapled by staples ejected from the second staplecavities 1315 b. The third staple cavities 1315 c are also positioned atregular intervals along a third longitudinal axis. The third staplecavities 1315 c are staggered with respect to the second staple cavities1315 b. The third staple cavities 1315 c are positioned laterally withrespect to the staple gaps in the second row of staple cavities 1315 b.

The staple cartridge body 1310 further comprises a tissue-supportingdeck 1314. The deck 1314 comprises a plurality of peaks and valleysdefined therein. Valleys 1319 a are aligned with the first staplecavities 1315 a, valleys 1319 b are aligned with the second staplecavities 1315 b, and valleys 1319 c are aligned with the third staplecavities 1315 c. Peaks 1316 a are aligned with the gaps between thefirst staple cavities 1315 a. Peaks 1316 b are aligned with the gapsbetween the second staple cavities 1315 b. Similarly, peaks 1316 c arealigned with the gaps between the third staple cavities 1315 c. Thepeaks 1316 a in the first row of staple cavities 1315 a can be connectedto the peaks 1316 b in the second row of staple cavities 1315 b.Similarly, the peaks 1316 b in the second row of staple cavities 1315 bcan be connected to the peaks 1316 c in the third row of staple cavities1315 c. The wells 1319 a, 1319 b, and 1319 c can each have the samedepth; however, other embodiments are envisioned in which the wells 1319a, 1319 b, and 1319 c have different depths. For instance, the wells1319 a aligned with the first staple cavities 1315 a can have a firstdepth, the wells 1319 b aligned with the second staple cavities 1315 bcan have a second depth, and the wells 1319 c aligned with the thirdstaple cavities 1315 c can have a third depth, wherein the first depth,the second depth, and/or the third depth can be different. The peaks1316 a positioned between the first staple cavities 1315 a have a firstheight, the peaks 1316 b positioned between the second staple cavities1315 b have a second height, and the peaks 1316 c positioned between thethird staple cavities 1315 c have a third height, wherein the firstheight, the second height, and/or the third height can be different. Thefirst height of the peaks 1316 a is taller than the second height of thepeaks 1316 b and the third height of the peaks 1316 c, for example. Thesecond height of the peaks 1316 b can be taller than the third height ofthe peaks 1316 c, for example. Such an arrangement can apply a firstpressure to the tissue positioned over the staple cavities 1315 a, asecond pressure to the tissue positioned over the staple cavities 1315b, and a third pressure to the tissue positioned over the staplecavities 1315 c. The first pressure is greater than the second pressureand the second pressure is greater than the third pressure. Such apressure gradient can push fluids away from the incision created by theknife passing through the longitudinal slot 1313.

The staple cartridge 1300 can be utilized with any suitable layer thatcan be implanted against the tissue being stapled. The layer cancomprise an adjunct material which is positioned on the deck 1314 of thecartridge body 1310 before the staple cartridge 1300 is inserted intothe patient. Such an adjunct material could comprise buttress materialand/or a tissue thickness compensator, for example. In variousinstances, the layer can move relative to the deck 1314 when the staplecartridge 1300 and the layer are positioned relative to the tissue thatis to be stapled.

Turning now to FIG. 22A, a layer 1320 comprises a bottom surface 1324configured to contact and be supported by the deck 1314 of the cartridgebody 1310. The bottom surface 1324 comprises peaks 1329 extendingtherefrom which are configured to be received in the valleys 1319 a-1319c defined in the deck 1314. The peaks 1329 can limit relative motionbetween the layer 1320 and the cartridge body 1310. The peaks 1329 areclosely received within the valleys 1319 a-1319 c and, as a result, thepeaks 1329 can abut the walls of the valleys 1319 a-1319 c to limitlateral and/or longitudinal movement of the layer 1320. The bottomsurface 1324 further comprises valleys 1326 defined therein which areconfigured to receive peaks 1316 a-1316 c extending from the cartridgebody 1310. The valleys 1326 can limit relative motion between the layer1320 and the cartridge body 1310. The peaks 1316 a-1316 c are closelyreceived within the valleys 1326 and, as a result, the peaks 1316 a-1316c can abut the walls of the valleys 1326 to limit lateral and/orlongitudinal movement of the layer 1320.

In addition to or in lieu of the above, the layer 1320 is closelyreceived between a proximal wall 1317 and a distal wall 1318 of thecartridge body 1310 and, as a result, the layer 1320 can abut theproximal wall 1317 and/or the distal wall 1318 to limit longitudinalmovement of the layer 1320. The layer 1320 comprises a proximal end wall1327 configured to engage the proximal wall 1317 and a distal end wall1328 configured to engage the distal wall 1318. The layer 1320 can besized and configured such that it is compressed, or wedged, between theproximal wall 1317 and the distal wall 1318. Such compression, orwedging, can not only limit the longitudinal movement of the layer 1320,it can also limit unintentional vertical movement of the layer 1320 awayfrom the deck 1314. The longitudinal compression, or wedging, issufficient to hold the layer 1320 in position yet, at the same, it canbe overcome to permit the layer 1320 to be separated from the cartridgebody 1310 after the staples have been fired and the layer 1320 has beenimplanted against the tissue.

The valleys 1326 and the peaks 1329 comprise a negative impression ofthe peaks 1316 a-1316 c and the valleys 1319 a-1319 c, respectively;however, the layer 1320 can comprise any suitable configuration. Thevalleys 1326 and the peaks 1329 are defined by contours which cause thevalleys 1326 and the peaks 1329 to fit snugly within the peaks 1316a-1316 c and the valleys 1319 a-1319 c, respectively.

Each staple cavity 1315 a, 1315 b, and 1315 c is configured to removablystore a staple therein. In various instances, the staples stored in thestaple cavities 1315 a, 1315 b, and 1315 c have the same unformedheight. In certain instances, such staples can be deformed to the sameformed height. In other instances, such staples can be deformed todifferent formed heights. For example, the staples ejected from thefirst staple cavities 1315 a can be deformed to a first deformed height,the staples ejected from the second staple cavities 1315 b can bedeformed to a second deformed height, and the staples ejected from thethird staple cavities 1315 c can be deformed to a third deformed height.The first deformed height can be shorter than the second deformed heightand the second deformed height can be shorter than the third deformedheight. Such an arrangement can provide a tissue compression gradientwith respect to an incision made in the tissue. In various instances,the staples stored in the staple cavities 1315 a, 1315 b, and 1315 c canhave different unformed heights. For example, the staples ejected fromthe first staple cavities 1315 a can have a first unformed height, thestaples ejected from the second staple cavities 1315 b can have a secondunformed height, and the staples ejected from the third staple cavities1315 c can have a third unformed height. The first unformed height canbe shorter than the second unformed height and the second unformedheight can be shorter than the third unformed height.

A staple cartridge assembly 1500 is depicted in FIGS. 33-35. The staplecartridge assembly 1500 comprises a cartridge body 1510 and a layer1520. The cartridge body 1510 comprises a proximal end 1511 and a distalend 1512. The cartridge body 1510 further comprises a longitudinal slot1513 defined therein which is configured to receive at least a portionof a firing member therein. The slot 1513 extends from the proximal end1511 toward the distal end 1512. The cartridge body 1510 furthercomprises a plurality of staple cavities 1515 defined in a deck 1514 ofthe cartridge body 1510. The staple cavities 1515 are arranged in threelongitudinal rows on a first side of the longitudinal slot 1513 andthree longitudinal rows on a second side of the longitudinal slot 1513.Further to the above, the firing member can be configured to lift stapledrivers positioned within the cartridge body 1510 to eject staplesremovably stored in the staple cavities 1515 as the firing member ismoved toward the distal end 1512 of the staple cartridge 1500.

The cartridge body 1510 further comprises projections 1519 which extendupwardly from the deck 1514. The projections 1519 extend the staplecavities 1515 above the deck 1514. The projections 1519 can support thestaples stored in the staple cavities 1515 before, during, and/or afterthey are lifted toward the anvil by the staple drivers. The projections1519 can guide the staples as the staples are lifted toward the anvil. Aprojection 1519 can be positioned at a proximal end of a staple cavity1515, at a distal end of a staple cavity 1515, and/or at both ends of astaple cavity 1515. All of the staple cavities 1515 depicted in FIGS.33-35 are surrounded at both ends by a projection 1519; however, otherembodiments are envisioned in which some of the staple cavities 1515 aresurrounded by two projections, one projection, and/or no projections.

The projections 1519 are arranged in longitudinal rows correspondingwith the longitudinal rows of staple cavities 1515. Various embodimentsare envisioned in which the cartridge body 1510 comprises an equalnumber of rows of projections 1519 and rows of staple cavities 1515. Forexample, six rows of projections 1519 are aligned with six rows ofstaple cavities 1515. Other embodiments are envisioned in which thecartridge body 1510 comprises more rows of staple cavities 1515 thanrows of projections 1519. For example, a row of projections 1519 may bealigned with each of the innermost rows of staple cavities 1515 whilethe outermost rows of staple cavities 1515 may not have rows ofprojections aligned therewith. Certain embodiments are envisioned inwhich a projection, or a row of projections, is laterally offset withrespect to a staple cavity, or a row of staple cavities.

Referring again to FIGS. 33-35, the layer 1520 comprises a proximal end1521 positioned adjacent the proximal end 1511 of the cartridge body1510 and, in addition, a distal end 1522 positioned adjacent the distalend 1511 of the cartridge body 1510. The layer 1520 further comprises abottom surface 1524 configured to contact and be supported by the deck1514 of the cartridge body 1510 and, in addition, a tissue-contactingsurface 1526 positioned on the opposite side thereof. Thetissue-contacting surface 1526 comprises a flat surface; however, otherembodiments are envisioned in which the tissue-contacting surfacecomprises a textured and/or gripping surface configured to reduceundesired relative sliding motion between the tissue and the layer 1520.The layer 1520 further comprises a longitudinal slot 1523 aligned, oralignable, with the slot 1513 defined in the cartridge body 1510. Theslot 1523 defines a portion of the layer 1520 which comprises a reducedcross-sectional thickness of the layer 1520 that is incised by a cuttingmember of the firing member than passes through the slot 1513 of thecartridge body 1510. The reduction in cross-section provided by the slot1523 facilitates the transection of the layer 1520.

The layer 1520 comprises a plurality of longitudinal slots 1529 definedtherein. The slots 1529 are defined in the bottom surface 1524 and arealigned with the rows of projections 1519. The slots 1529 are alsoaligned with the staple cavities 1515. The layer 1520 comprises sixslots 1529 aligned with the six rows of projections 1519 and the sixrows of staple cavities 1515, for example. When staples are ejected fromthe staple cavities 1515, the staples can enter the slots 1529 andpierce the layer 1520. When the staples are deformed by an anvil, thestaples can capture the portions of the layer 1520 that include thelongitudinal slots 1529 therein. Each slot 1529 can extend between theproximal end 1521 and the distal end 1522 of the layer 1520; however,other embodiments are envisioned in which the slots 1529 extend lessthan the entire length of the layer 1520. For instance, the proximalends and/or the distal ends of the slots 1529 may be closed off, orblocked. The configuration of the slots 1529 can be selected so as toprovide an appropriate tissue thickness compensation when the layer 1520comprises a tissue thickness compensator.

Each slot 1529 is defined by a slot width W and a slot depth D. Invarious embodiments, the slot width W can be sized and configured suchthat the side walls of the slots 1529 can engage the projections 1519.In at least one such embodiment, the projections 1519 can be press-fitwithin the slots 1529 wherein the layer 1520 can be releasably held tothe cartridge body 1510 by the interaction between the projections 1519and the slots 1529. In other embodiments, the slot width W can be sizedand configured such there is a clearance-fit between the side walls ofthe slots 1529 and the projections 1519.

In various embodiments, further to the above, the slot depth D can besized and configured such that the bottom walls of the slots 1529contact the top surfaces of the projections 1519. In at least oneinstance, the bottom walls of the slots 1529 can contact the topsurfaces of the projections 1519 when the bottom surface 1524 of thelayer 1520 is in contact with the deck 1514. In certain other instances,the bottom surface 1524 of the layer 1520 may not be in contact with thedeck 1514 when the bottom surfaces of the slots 1529 are positionedagainst the top surfaces of the projections 1519. In such instances, thelayer 1520 can be held in an elevated position above the deck 1514. Inuse, the compressive pressure applied to the layer 1520 when tissue isclamped between the staple cartridge 1500 and an anvil can push thelayer 1520 toward the deck 1514. In certain instances, the bottom wallsof the slots 1529 may not be in contact with the projections 1519 whenthe bottom surface 1524 of the layer 1520 is positioned against the deck1514. Similar to the above, the compressive pressure applied to thelayer 1520 when tissue is clamped between the staple cartridge 1500 andan anvil can push the bottom surfaces of the slots 1529 against theprojections 1519.

Referring again to FIG. 35, the longitudinal slots 1529 defined in thelayer 1520 define portions of the layer 1520 having a cross-sectionwhich is thinner than the cross-sections of the other portions of thelayer 1520. Turning now to FIG. 36, a layer 1620 comprises a distal end1622, a bottom surface 1624, a top surface 1626, and a longitudinal slot1623 defined therein which is aligned, or alignable, with thelongitudinal slot 1513 defined in the cartridge body 1510, for example.Similar to the above, the layer 1620 comprises longitudinal slots 1629which are aligned, or alignable, with the longitudinal rows ofprojections 1519 extending from the cartridge body 1510. The layer 1620further comprises ridges 1628 extending from the top surface 1626. Theridges 1628 are aligned, or at least substantially aligned, with theslots 1629. The ridges 1628 increase the cross-section of the portionsof the layer 1620 including the longitudinal slots 1629. The ridges 1628are also aligned with the staple cavities 1515. When staples, such asstaples 1630, for example, are ejected from the staple cavities 1515,the staples 1630 can capture the portions of the layer 1620 includingthe slots 1629 and the ridges 1628.

As illustrated in FIG. 36, the slots 1629 decrease the cross-sectionalthickness of the layer 1620 more than the ridges 1628 increase thecross-sectional thickness of the layer 1620, for example. In otherembodiments, the slots 1629 can decrease the cross-sectional thicknessof the layer 1620 less than the ridges 1628 increase the cross-sectionalthickness of the layer 1620, for example. In certain embodiments, theslots 1629 can decrease the cross-sectional thickness of the layer 1620the same amount that the ridges 1628 increase the cross-sectionalthickness of the layer 1620, for example. The configuration of theridges 1628 and the slots 1629 can be selected so as to provide theappropriate tissue thickness compensation when the layer 1620 comprisesa tissue thickness compensator.

Referring again to FIG. 35, the layer 1520 is comprised of a singlepiece of material; however, other embodiments are envisioned in which alayer is comprised of two or more pieces of material that have beenassembled together. Turning now to FIG. 37, a layer 1720 comprisesinserts 1728 which are aligned with the longitudinal slots 1629 of thelayer 1720 and the staple cavities 1515 of the cartridge body 1510, forexample. The inserts 1728 are embedded in the layer 1720. In at leastone instance, the layer 1720 can be molded around the inserts 1728. Incertain instances, the layer 1720 can include grooves defined thereinwherein the inserts 1728 can be positioned in the grooves. In at leastone such instance, at least one adhesive could be utilized to hold theinserts 1728 in the grooves. The inserts 1728 are comprised of adifferent material than the other portions of the layer 1720; however,other embodiments are envisioned in which they are comprised of the samematerial. The inserts 1728 are comprised of a denser material than theother portions of the layer 1720; however, other embodiments areenvisioned in which the inserts 1728 comprise any suitable density.Similar to the above, the staples 1630, for example, can be configuredto capture the inserts 1728 therein when the staples 1630 are deformed.The configuration of the inserts 1728 can be selected so as to providethe appropriate tissue thickness compensation when the layer 1720comprises a tissue thickness compensator.

In various instances, a layer of material can comprise buttress materialand/or a tissue thickness compensator, for example. The layer ofmaterial can be comprised of Gore SeamGuard material, SynovisPeri-Strips material, and/or polyurethane, for example. The entiredisclosure of U.S. patent application Ser. No. 13/763,095, entitledLAYER ARRANGEMENTS FOR SURGICAL STAPLE CARTRIDGES, filed on Feb. 28,2013, now U.S. Pat. No. 9,770,245, is incorporated by reference herein.The entire disclosures of U.S. patent application Ser. No. 13/531,619,entitled TISSUE STAPLER HAVING A THICKNESS COMPENSATOR COMPRISINGINCORPORATING A HEMOSTATIC AGENT, filed on Jun. 25, 2012, now U.S. Pat.No. 9,345,477, U.S. patent application Ser. No. 13/531,623, entitledTISSUE STAPLER HAVING A THICKNESS COMPENSATOR INCORPORATING AN OXYGENGENERATING AGENT, filed on Jun. 25, 2012, now U.S. Pat. No. 9,320,518,U.S. patent application Ser. No. 13/531,627, entitled TISSUE STAPLERHAVING A THICKNESS COMPENSATOR INCORPORATING AN ANTI-MICROBIAL AGENT,filed on Jun. 25, 2012, now U.S. Pat. No. 9,307,965, and U.S. patentapplication Ser. No. 13/531,630, entitled TISSUE STAPLER HAVING ATHICKNESS COMPENSATOR INCORPORATING AN ANTI-INFLAMMATORY AGENT, filed onJun. 25, 2012, now U.S. Pat. No. 9,314,246, are incorporated byreference herein. A layer can be comprised of a bioabsorbable materialand/or a non-bioabsorbable material. In some instances, a layer ofmaterial can be attached to the deck. In at least one instance, at leastone adhesive can be utilized to releasably adhere the layer to the deck.In some instances, the layer of material can be releasably attached tothe deck utilizing one or more sutures or straps, for example. Incertain instances, the layer can comprise a solid piece of material. Insome instances, the layer can include apertures defined therein.

Further to the above, the staples being deployed from a staple cartridgecan puncture the layer before entering into the tissue. The staples mayalso re-puncture the layer as they are being deformed by the anvil. Invarious instances, thicker or more puncture-resistant strips of polymercould be integrated into the layer, for example. For instance, suchstrips could be integrated into the tissue-contacting surface of thelayer. In at least one instance, each strip could be 0.003″ thick andcomprised of 90/10 PLA/PCL, for example. In certain instances, eachstrip could be 0.006″ thick 25/75 PGA/PCL, for example. The strips couldbe welded into the foam as part of a felting process, for example. Thedisclosure of U.S. patent application Ser. No. 14/187,383, entitledIMPLANTABLE LAYERS AND METHODS FOR ALTERING IMPLANTABLE LAYERS FOR USEWITH SURGICAL FASTENING INSTRUMENTS, now U.S. Pat. No. 9,839,422, isincorporated by reference in its entirety. The felting process couldserve another purpose which is to create a closed cell foam and/or acontinuous tissue contacting surface. In some instances, separate thinfilm strips could be welded into the tissue-contacting side of the foam.The various methods disclosed herein can create a composite absorbablematerial with features or zones aligned with the staples that havediffering properties for initial staple puncturing, forming, andre-piercing.

A layer, such as buttress material, for example, may be made from anybiocompatible material. Buttress material may be formed from a naturalmaterial and/or a synthetic material. Buttress material may bebioabsorbable and/or non-bioabsorbable. It should be understood that anycombination of natural, synthetic, bioabsorbable and non-bioabsorbablematerials may be used to form buttress material. Some non-limitingexamples of materials from which the buttress material may be madeinclude, but are not limited to, poly(lactic acid), poly (glycolicacid), poly (hydroxybutyrate), poly (phosphazine), polyesters,polyethylene glycols, polyethylene oxides, polyacrylamides,polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinylalcohols, polyacrylic acid, polyacetate, polycaprolactone,polypropylene, aliphatic polyesters, glycerols, poly(amino acids),copoly (ether-esters), polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkylene oxalates, polyoxaesters,polyorthoesters, polyphosphazenes and copolymers, block copolymers,homopolymers, blends and/or combinations thereof, for example.

Natural biological polymers can be used in forming the buttressmaterial. Suitable natural biological polymers include, but are notlimited to, collagen, gelatin, fibrin, fibrinogen, elastin, keratin,albumin, hydroxyethyl cellulose, cellulose, oxidized cellulose,hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethylcellulose, chitan, chitosan, and/or combinations thereof, for example.Natural biological polymers may be combined with any of the otherpolymeric materials described herein to produce the buttress material.Collagen of human and/or animal origin, e.g., type I porcine or bovinecollagen, type I human collagen or type III human collagen may be usedto form the buttress material. The buttress material may be made fromdenatured collagen or collagen which has at least partially lost itshelical structure through heating or any other method, consisting mainlyof non-hydrated chains, of molecular weight close to 100 kDa, forexample. The term “denatured collagen” means collagen which has lost itshelical structure. The collagen used for the porous layer as describedherein may be native collagen or atellocollagen, notably as obtainedthrough pepsin digestion and/or after moderate heating as definedpreviously, for example. The collagen may have been previouslychemically modified by oxidation, methylation, succinylation, ethylationand/or any other known process.

Where the buttress material is fibrous, the fibers may be filaments orthreads suitable for knitting or weaving or may be staple fibers, suchas those frequently used for preparing non-woven materials. The fibersmay be made from any biocompatible material. The fibers may be formedfrom a natural material or a synthetic material. The material from whichthe fibers are formed may be bioabsorbable or non-bioabsorbable. Itshould be understood that any combination of natural, synthetic,bioabsorbable and non-bioabsorbable materials may be used to form thefibers. Some non-limiting examples of materials from which the fibersmay be made include, but are not limited to, poly(lactic acid), poly(glycolic acid), poly (hydroxybutyrate), poly (phosphazine), polyesters,polyethylene glycols, polyethylene oxides, polyacrylamides,polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinylalcohols, polyacrylic acid, polyacetate, polycaprolactone,polypropylene, aliphatic polyesters, glycerols, poly(amino acids),copoly (ether-esters), polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkylene oxalates, polyoxaesters,polyorthoesters, polyphosphazenes and copolymers, block copolymers,homopolymers, blends and/or combinations thereof. Where the buttressmaterial is fibrous, the buttress material may be formed using anymethod suitable to forming fibrous structures including, but not limitedto, knitting, weaving, non-woven techniques and the like, for example.Where the buttress material is a foam, the porous layer may be formedusing any method suitable to forming a foam or sponge including, but notlimited to the lyophilization or freeze-drying of a composition, forexample.

The buttress material may possesses haemostatic properties. Illustrativeexamples of materials which may be used in providing the buttressmaterial with the capacity to assist in stopping bleeding or hemorrhageinclude, but are not limited to, poly(lactic acid), poly(glycolic acid),poly(hydroxybutyrate), poly(caprolactone), poly(dioxanone),polyalkyleneoxides, copoly(ether-esters), collagen, gelatin, thrombin,fibrin, fibrinogen, fibronectin, elastin, albumin, hemoglobin,ovalbumin, polysaccharides, hyaluronic acid, chondroitin sulfate,hydroxyethyl starch, hydroxyethyl cellulose, cellulose, oxidizedcellulose, hydroxypropyl cellulose, carboxyethyl cellulose,carboxymethyl cellulose, chitan, chitosan, agarose, maltose,maltodextrin, alginate, clotting factors, methacrylate, polyurethanes,cyanoacrylates, platelet agonists, vasoconstrictors, alum, calcium, RGDpeptides, proteins, protamine sulfate, epsilon amino caproic acid,ferric sulfate, ferric subsulfates, ferric chloride, zinc, zincchloride, aluminum chloride, aluminum sulfates, aluminum acetates,permanganates, tannins, bone wax, polyethylene glycols, fucans and/orcombinations thereof, for example. The use of natural biologicalpolymers, and in particular proteins, may be useful in forming buttressmaterial having haemostatic properties. Suitable natural biologicalpolymers include, but are not limited to, collagen, gelatin, fibrin,fibrinogen, elastin, keratin, albumin and/or combinations thereof, forexample. Natural biological polymers may be combined with any otherhaemostatic agent to produce the porous layer of the buttress. Theentire disclosure of U.S. Pat. No. 8,496,683, entitled BUTTRESS ANDSURGICAL STAPLING APPARATUS, which issued on Jul. 30, 2013, isincorporated by reference herein.

In various circumstances, the tissue thickness compensator assembly maycomprise a polymeric composition. The polymeric composition may compriseone or more synthetic polymer and/or one or more non-synthetic polymer.The synthetic polymer may comprise a synthetic absorbable polymer and/ora synthetic non-absorbable polymer. In various circumstances, thepolymeric composition may comprise a biocompatible foam, for example.The biocompatible foam may comprise a porous, open cell foam and/or aporous, closed cell foam, for example. The biocompatible foam can have auniform pore morphology or may have a gradient pore morphology (i.e.small pores gradually increasing in size to large pores across thethickness of the foam in one direction). In various circumstances, thepolymeric composition may comprise one or more of a porous scaffold, aporous matrix, a gel matrix, a hydrogel matrix, a solution matrix, afilamentous matrix, a tubular matrix, a composite matrix, a membranousmatrix, a biostable polymer, and a biodegradable polymer, andcombinations thereof. For example, the tissue thickness compensatorassembly may comprise a foam reinforced by a filamentous matrix or maycomprise a foam having an additional hydrogel layer that expands in thepresence of bodily fluids to further provide the compression on thetissue. In various circumstances, a tissue thickness compensatorassembly could also be comprised of a coating on a material and/or asecond or third layer that expands in the presence of bodily fluids tofurther provide the compression on the tissue. Such a layer could be ahydrogel that could be a synthetic and/or naturally derived material andcould be either biodurable and/or biodegradable, for example. In certaincircumstances, a tissue thickness compensator assembly could bereinforced with fibrous non-woven materials or fibrous mesh typeelements, for example, that can provide additional flexibility,stiffness, and/or strength. In various circumstances, a tissue thicknesscompensator assembly that has a porous morphology which exhibits agradient structure such as, for example, small pores on one surface andlarger pores on the other surface. Such morphology could be more optimalfor tissue in-growth or hemostatic behavior. Further, the gradient couldbe also compositional with a varying bio-absorption profile. A shortterm absorption profile may be preferred to address hemostasis while along term absorption profile may address better tissue healing withoutleakages.

Examples of non-synthetic polymers include, but are not limited to,lyophilized polysaccharide, glycoprotein, elastin, proteoglycan,gelatin, collagen, and oxidized regenerated cellulose (ORC). Examples ofsynthetic absorbable polymers include, but are not limited to,poly(lactic acid) (PLA), poly(L-lactic acid) (PLLA), polycaprolactone(PCL), polyglycolic acid (PGA), poly(trimethylene carbonate) (TMC),polyethylene terephthalate (PET), polyhydroxyalkanoate (PHA), acopolymer of glycolide and ϵ-caprolactone (PGCL), a copolymer ofglycolide and-trimethylene carbonate, poly(glycerol sebacate) (PGS),polydioxanone, poly(orthoesters), polyanhydrides, polysaccharides,poly(ester-am ides), tyrosine-based polyarylates, tyrosine-basedpolyiminocarbonates, tyrosine-based polycarbonates,poly(D,L-lactide-urethane), poly(B-hydroxybutyrate),poly(E-caprolactone), polyethyleneglycol (PEG),poly[bis(carboxylatophenoxy) phosphazene], poly(amino acids),pseudo-poly(amino acids), absorbable polyurethanes, and combinationsthereof. In various circumstances, the polymeric composition maycomprise from approximately 50% to approximately 90% by weight of thepolymeric composition of PLLA and approximately 50% to approximately 10%by weight of the polymeric composition of PCL, for example. In at leastone embodiment, the polymeric composition may comprise approximately 70%by weight of PLLA and approximately 30% by weight of PCL, for example.In various circumstances, the polymeric composition may comprise fromapproximately 55% to approximately 85% by weight of the polymericcomposition of PGA and 15% to 45% by weight of the polymeric compositionof PCL, for example. In at least one embodiment, the polymericcomposition may comprise approximately 65% by weight of PGA andapproximately 35% by weight of PCL, for example. In variouscircumstances, the polymeric composition may comprise from approximately90% to approximately 95% by weight of the polymeric composition of PGAand approximately 5% to approximately 10% by weight of the polymericcomposition of PLA, for example.

In various circumstances, the synthetic absorbable polymer may comprisea bioabsorbable, biocompatible elastomeric copolymer. Suitablebioabsorbable, biocompatible elastomeric copolymers include but are notlimited to copolymers of epsilon-caprolactone and glycolide (preferablyhaving a mole ratio of epsilon-caprolactone to glycolide of from about30:70 to about 70:30, preferably 35:65 to about 65:35, and morepreferably 45:55 to 35:65); elastomeric copolymers ofepsilon-caprolactone and lactide, including L-lactide, D-lactide blendsthereof or lactic acid copolymers (preferably having a mole ratio ofepsilon-caprolactone to lactide of from about 35:65 to about 65:35 andmore preferably 45:55 to 30:70) elastomeric copolymers of p-dioxanone(1,4-dioxan-2-one) and lactide including L-lactide, D-lactide and lacticacid (preferably having a mole ratio of p-dioxanone to lactide of fromabout 40:60 to about 60:40); elastomeric copolymers ofepsilon-caprolactone and p-dioxanone (preferably having a mole ratio ofepsilon-caprolactone to p-dioxanone of from about 30:70 to about 70:30);elastomeric copolymers of p-dioxanone and trimethylene carbonate(preferably having a mole ratio of p-dioxanone to trimethylene carbonateof from about 30:70 to about 70:30); elastomeric copolymers oftrimethylene carbonate and glycolide (preferably having a mole ratio oftrimethylene carbonate to glycolide of from about 30:70 to about 70:30);elastomeric copolymer of trimethylene carbonate and lactide includingL-lactide, D-lactide, blends thereof or lactic acid copolymers(preferably having a mole ratio of trimethylene carbonate to lactide offrom about 30:70 to about 70:30) and blends thereof. In one embodiment,the elastomeric copolymer is a copolymer of glycolide andepsilon-caprolactone. In another embodiment, the elastomeric copolymeris a copolymer of lactide and epsilon-caprolactone.

The disclosures of U.S. Pat. No. 5,468,253, entitled ELASTOMERIC MEDICALDEVICE, which issued on Nov. 21, 1995, and U.S. Pat. No. 6,325,810,entitled FOAM BUTTRESS FOR STAPLING APPARATUS, which issued on Dec. 4,2001, are hereby incorporated by reference in their respectiveentireties.

In various circumstances, the synthetic absorbable polymer may compriseone or more of 90/10 poly(glycolide-L-lactide) copolymer, commerciallyavailable from Ethicon, Inc. under the trade designation VICRYL(polyglactic 910), polyglycolide, commercially available from AmericanCyanamid Co. under the trade designation DEXON, polydioxanone,commercially available from Ethicon, Inc. under the trade designationPDS, poly(glycolide-trimethylene carbonate) random block copolymer,commercially available from American Cyanamid Co. under the tradedesignation MAXON, 75/25poly(glycolide-E-caprolactone-poliglecaprolactone 25) copolymer,commercially available from Ethicon under the trade designationMONOCRYL, for example.

Examples of synthetic non-absorbable polymers include, but are notlimited to, foamed polyurethane, polypropylene (PP), polyethylene (PE),polycarbonate, polyamides, such as nylon, polyvinylchloride (PVC),polymethylmetacrylate (PMMA), polystyrene (PS), polyester,polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE),polytrifluorochloroethylene (PTFCE), polyvinylfluoride (PVF),fluorinated ethylene propylene (FEP), polyacetal, polysulfone, andcombinations thereof. The synthetic non-absorbable polymers may include,but are not limited to, foamed elastomers and porous elastomers, suchas, for example, silicone, polyisoprene, and rubber. In variouscircumstances, the synthetic polymers may comprise expandedpolytetrafluoroethylene (ePTFE), commercially available from W. L. Gore& Associates, Inc. under the trade designation GORE-TEX Soft TissuePatch and co-polyetherester urethane foam commercially available fromPolyganics under the trade designation NASOPORE.

The polymeric composition of a tissue thickness compensator assembly maybe characterized by percent porosity, pore size, and/or hardness, forexample. In various circumstances, the polymeric composition may have apercent porosity from approximately 30% by volume to approximately 99%by volume, for example. In certain circumstances, the polymericcomposition may have a percent porosity from approximately 60% by volumeto approximately 98% by volume, for example. In various circumstances,the polymeric composition may have a percent porosity from approximately85% by volume to approximately 97% by volume, for example. In at leastone embodiment, the polymeric composition may comprise approximately 70%by weight of PLLA and approximately 30% by weight of PCL, for example,and can comprise approximately 90% porosity by volume, for example. Inat least one such embodiment, as a result, the polymeric compositionwould comprise approximately 10% copolymer by volume. In at least oneembodiment, the polymeric composition may comprise approximately 65% byweight of PGA and approximately 35% by weight of PCL, for example, andcan have a percent porosity from approximately 93% by volume toapproximately 95% by volume, for example. In various circumstances, thepolymeric composition may comprise a greater than 85% porosity byvolume. The polymeric composition may have a pore size fromapproximately 5 micrometers to approximately 2000 micrometers, forexample. In various circumstances, the polymeric composition may have apore size between approximately 10 micrometers to approximately 100micrometers, for example. In at least one such embodiment, the polymericcomposition can comprise a copolymer of PGA and PCL, for example. Incertain circumstances, the polymeric composition may have a pore sizebetween approximately 100 micrometers to approximately 1000 micrometers,for example. In at least one such embodiment, the polymeric compositioncan comprise a copolymer of PLLA and PCL, for example. According tocertain aspects, the hardness of a polymeric composition may beexpressed in terms of the Shore Hardness, which can defined as theresistance to permanent indentation of a material as determined with adurometer, such as a Shore Durometer. In order to assess the durometervalue for a given material, a pressure is applied to the material with adurometer indenter foot in accordance with ASTM procedure D2240-00,entitled, “Standard Test Method for Rubber Property-Durometer Hardness”,the entirety of which is incorporated herein by reference. The durometerindenter foot may be applied to the material for a sufficient period oftime, such as 15 seconds, for example, wherein a reading is then takenfrom the appropriate scale. Depending on the type of scale being used, areading of 0 can be obtained when the indenter foot completelypenetrates the material, and a reading of 100 can be obtained when nopenetration into the material occurs. This reading is dimensionless. Invarious circumstances, the durometer may be determined in accordancewith any suitable scale, such as Type A and/or Type OO scales, forexample, in accordance with ASTM D2240-00. In various circumstances, thepolymeric composition of a tissue thickness compensator assembly mayhave a Shore A hardness value from approximately 4 A to approximately 16A, for example, which is approximately 45 OO to approximately 65 OO onthe Shore OO range. In at least one such embodiment, the polymericcomposition can comprise a PLLA/PCL copolymer or a PGA/PCL copolymer,for example. In various circumstances, the polymeric composition of atissue thickness compensator assembly may have a Shore A Hardness valueof less than 15 A. In various circumstances, the polymeric compositionof a tissue thickness compensator assembly may have a Shore A Hardnessvalue of less than 10 A. In various circumstances, the polymericcomposition of a tissue thickness compensator assembly may have a ShoreA Hardness value of less than 5 A. In certain circumstances, thepolymeric material may have a Shore OO composition value fromapproximately 35 OO to approximately 75 OO, for example.

In various circumstances, the polymeric composition may have at leasttwo of the above-identified properties. In various circumstances, thepolymeric composition may have at least three of the above-identifiedproperties. The polymeric composition may have a porosity from 85% to97% by volume, a pore size from 5 micrometers to 2000 micrometers, and aShore A hardness value from 4 A to 16 A and Shore OO hardness value from45 OO to 65 OO, for example. In at least one embodiment, the polymericcomposition may comprise 70% by weight of the polymeric composition ofPLLA and 30% by weight of the polymeric composition of PCL having aporosity of 90% by volume, a pore size from 100 micrometers to 1000micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OOhardness value from 45 00 to 65 OO, for example. In at least oneembodiment, the polymeric composition may comprise 65% by weight of thepolymeric composition of PGA and 35% by weight of the polymericcomposition of PCL having a porosity from 93% to 95% by volume, a poresize from 10 micrometers to 100 micrometers, and a Shore A hardnessvalue from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO,for example.

In various circumstances, the polymeric composition may comprise apharmaceutically active agent. The polymeric composition may release atherapeutically effective amount of the pharmaceutically active agent.In various circumstances, the pharmaceutically active agent may bereleased as the polymeric composition is desorbed/absorbed. In variouscircumstances, the pharmaceutically active agent may be released intofluid, such as, for example, blood, passing over or through thepolymeric composition. Examples of pharmaceutically active agents mayinclude, but are not limited to, hemostatic agents and drugs, such as,for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC);anti-inflammatory drugs, such as, for example, diclofenac, aspirin,naproxen, sulindac, and hydrocortisone; antibiotic and antimicrobialdrug or agents, such as, for example, triclosan, ionic silver,ampicillin, gentamicin, polymyxin B, chloramphenicol; and anticanceragents, such as, for example, cisplatin, mitomycin, adriamycin.

Various methods are disclosed herein for manufacturing a tissuethickness compensator. Such methods could be used to manufacture anysuitable layer for use with a fastener cartridge and/or a surgicalfastening instrument, for example. Such a layer can comprise a less thanone hundred percent dense composition which can be created utilizing anysuitable process. For instance, such processes can include, for example,extruding, injection molding, weaving, lyophilization, gas-foaming,and/or melt-blowing processes. Some processes may produce a foam whileother processes may not produce a foam; however, in any event, all suchembodiments are contemplated for use with all of the embodimentsdisclosed herein.

The entire disclosures of:

U.S. Pat. No. 5,403,312, entitled ELECTROSURGICAL HEMOSTATIC DEVICE,which issued on Apr. 4, 1995;

U.S. Pat. No. 7,000,818, entitled SURGICAL STAPLING INSTRUMENT HAVINGSEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, which issued on Feb. 21,2006;

U.S. Pat. No. 7,422,139, entitled MOTOR-DRIVEN SURGICAL CUTTING ANDFASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, which issued onSep. 9, 2008;

U.S. Pat. No. 7,464,849, entitled ELECTRO-MECHANICAL SURGICAL INSTRUMENTWITH CLOSURE SYSTEM AND ANVIL ALIGNMENT COMPONENTS, which issued on Dec.16, 2008;

U.S. Pat. No. 7,670,334, entitled SURGICAL INSTRUMENT HAVING ANARTICULATING END EFFECTOR, which issued on Mar. 2, 2010;

U.S. Pat. No. 7,753,245, entitled SURGICAL STAPLING INSTRUMENTS, whichissued on Jul. 13, 2010;

U.S. Pat. No. 8,393,514, entitled SELECTIVELY ORIENTABLE IMPLANTABLEFASTENER CARTRIDGE, which issued on Mar. 12, 2013;

U.S. patent application Ser. No. 11/343,803, entitled SURGICALINSTRUMENT HAVING RECORDING CAPABILITIES; now U.S. Pat. No. 7,845,537;

U.S. patent application Ser. No. 12/031,573, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENT HAVING RF ELECTRODES, filed Feb. 14, 2008;

U.S. patent application Ser. No. 12/031,873, entitled END EFFECTORS FORA SURGICAL CUTTING AND STAPLING INSTRUMENT, filed Feb. 15, 2008, nowU.S. Patent No. 7,980,443;

U.S. patent application Ser. No. 12/235,782, entitled MOTOR-DRIVENSURGICAL CUTTING INSTRUMENT, now U.S. Pat. No. 8,210,411;

U.S. patent application Ser. No. 12/249,117, entitled POWERED SURGICALCUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM,now U.S. Pat. No. 8,608,045;

U.S. patent application Ser. No. 12/647,100, entitled MOTOR-DRIVENSURGICAL CUTTING INSTRUMENT WITH ELECTRIC ACTUATOR DIRECTIONAL CONTROLASSEMBLY, filed Dec. 24, 2009; now U.S. Pat. No. 8,220,688;

U.S. patent application Ser. No. 12/893,461, entitled STAPLE CARTRIDGE,filed Sep. 29, 2012, now U.S. Pat. No 8,733,613;

U.S. patent application Ser. No. 13/036,647, entitled SURGICAL STAPLINGINSTRUMENT, filed Feb. 28, 2011, now U.S. Pat. No. 8,561,870;

U.S. patent application Ser. No. 13/118,241, entitled SURGICAL STAPLINGINSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, now U.S. Pat.No. 9,072,535;

U.S. patent application Ser. No. 13/524,049, entitled ARTICULATABLESURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, filed on Jun. 15, 2012;now U.S. Pat. No. 9,101,358;

U.S. patent application Ser. No. 13/800,025, entitled STAPLE CARTRIDGETISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013; now U.S. Pat.No. 9,345,481;

U.S. Patent Application Serial No 13/800,067, entitled STAPLE CARTRIDGETISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013; now U.S. PatentApplication Publication No. 2014/0263552;

U.S. Patent Application Publication No. 2007/0175955, entitled SURGICALCUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM,filed Jan. 31, 2006; and

U.S. Patent Application Publication No. 2010/0264194, entitled SURGICALSTAPLING INSTRUMENT WITH AN ARTICULATABLE END EFFECTOR, filed Apr. 22,2010, now U.S. Pat. No. 8,308,040, are hereby incorporated by referenceherein.

Although the various embodiments of the devices have been describedherein in connection with certain disclosed embodiments, manymodifications and variations to those embodiments may be implemented.Also, where materials are disclosed for certain components, othermaterials may be used. Furthermore, according to various embodiments, asingle component may be replaced by multiple components, and multiplecomponents may be replaced by a single component, to perform a givenfunction or functions. The foregoing description and following claimsare intended to cover all such modification and variations.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

1. A staple cartridge, comprising: a cartridge body, comprising: a deckand a bottom surface opposite the deck; a plurality of staple cavities,wherein each staple cavity extends into the cartridge body from the deckto the bottom surface; and a plurality of wells, wherein each wellcomprises a lowermost surface, and wherein each well extends into thecartridge body from the deck to the lowermost surface of the well; aplurality of staples removably positioned in the staple cavities; and atissue thickness compensator releasably secured to the cartridge body,wherein the tissue thickness compensator comprises: a compensator body;and a plurality of extensions extending from the compensator body intothe wells, wherein at least one extension is compressed within one ofthe wells.
 2. The staple cartridge of claim 1, wherein at least onelowermost surface is positioned intermediate the deck and the bottomsurface of the cartridge body.
 3. The staple cartridge of claim 1,wherein each well surrounds at least one staple cavity.
 4. The staplecartridge of claim 1, wherein each well extends between at least twostaple cavities.
 5. A staple cartridge, comprising: a cartridge body,comprising: a plurality of staple cavities arranged in a plurality ofrows, wherein the plurality of rows comprises a first row and a secondrow; and a well defined into the cartridge body, wherein the wellextends between one of the staple cavities in the first row and one ofthe staple cavities in the second row; a plurality of staples removablypositioned in the staple cavities; and a tissue thickness compensatorreleasably secured to the cartridge body, wherein the tissue thicknesscompensator comprises: a compensator body; and an extension extendingfrom the compensator body into the well, wherein the extension iscompressed within the well.
 6. The staple cartridge of claim 5, whereinthe plurality of rows comprises a third row positioned intermediate thefirst row and the second row.
 7. The staple cartridge of claim 6,wherein the well surrounds the staple cavities in the third row.
 8. Thestaple cartridge of claim 5, wherein the well extends from a proximalportion of the cartridge body to a distal portion of the cartridge body.9. The staple cartridge of claim 5, further comprising a longitudinalslot extending at least partially through the cartridge body, whereinthe well is positioned on a first side of the longitudinal slot.
 10. Thestaple cartridge of claim 9, wherein the well comprises a first well,and wherein the cartridge body further comprises a second well on asecond side of the longitudinal slot.
 11. A staple cartridge,comprising: a cartridge body, comprising: a proximal end and a distalend; a knife slot extending from the proximal end toward the distal end;a plurality of staple cavities; and a plurality of recesses, whereineach recess surrounds at least one staple cavity; a plurality of staplesremovably positioned in the staple cavities; and a tissue thicknesscompensator releasably secured to the cartridge body, wherein the tissuethickness compensator comprises: a compensator body; and a plurality ofextensions extending from the compensator body into the recesses,wherein at least one extension is compressed within one of the recesses.12. The staple cartridge of claim 11, wherein each recess extends alonga row of staple cavities.
 13. The staple cartridge of claim 11, whereinat least one recess asymmetrically surrounds at least one staple cavity.14. The staple cartridge of claim 11, wherein the tissue thicknesscompensator further comprises a longitudinal projection extending fromthe compensator body, and wherein the longitudinal projection isreleasably retained within the longitudinal knife slot.
 15. The staplecartridge of claim 11, wherein each recess comprises a proximal wall, adistal wall, and a pair of sidewalls extending between the proximal walland the distal wall.
 16. The staple cartridge of claim 15, wherein eachextension is compressed between the proximal wall and the distal wall ofthe recess into which the extension extends.
 17. The staple cartridge ofclaim 11, further comprising a sled configured to move along thelongitudinal knife slot of the cartridge body to fire the staples fromthe staple cavities.
 18. The staple cartridge of claim 17, wherein aretention force between the extensions and the recesses secures thetissue thickness compensator to the cartridge body, and wherein a firingforce on the staples from the sled is configured to overcome theretention force to release the tissue thickness compensator from thecartridge body.
 19. (canceled)
 20. (canceled)